Full opinion text
CHAGARES, Circuit Judge. I. Introduction...174 II. Facts and Procedural History...174 III. Analysis...178 A. Sufficiency of the Evidence Challenge...179 B. Jury Instruction Challenges...182 1. Lack of a Specific Unanimity Instruction...183 2. "Death Results" Instruction...187 C. Substantive Challenges to the Prosecution of the Case...190 1. First Amendment...190 2. Venue in Delaware...194 D. Evidentiary Challenges...195 1. Family Court Opinion...195 2. Belford's Therapy Tapes and Emails...199 a. Therapy Sessions...199 b. Emails...200 c. Confrontation Clause...201 3. Testimony of FBI Case Agent...202 4. Exclusion of Polygraph Rebuttal Evidence...203 5. Character Evidence Cross-Examination...204 E. Sentencing Challenges...205 1. Fifth and Sixth Amendments...205 2. Official Victim Enhancement...206 3. Vulnerable Victim Enhancement...207 4. Eighth Amendment...208 IV. Conclusion...208 I. Introduction This case concerns challenges by David Matusiewicz and Amy Gonzalez (together, the "defendants") to their convictions for conspiracy to commit interstate stalking and cyberstalking, interstate stalking resulting in death, and cyber stalking resulting in death, and to their resulting life sentences for conspiracy to commit interstate stalking and cyberstalking which resulted in the death of Christine Belford, the ex-wife of David Matusiewicz. The defendants are siblings and were indicted, along with their mother, Lenore Matusiewicz, after their father, Thomas Matusiewicz, shot and killed Belford and himself in the lobby of the New Castle County Courthouse. They engaged in a years-long conspiracy with Thomas Matusiewicz, an unindicted co-conspirator, to harass Belford, which ultimately resulted in her death. On appeal, each defendant challenges, inter alia, the constitutionality of the statutes under which they were convicted, the jury's verdict on sufficiency of the evidence grounds, various evidentiary rulings of the District Court, as well as numerous challenges to their sentences of life imprisonment. Faced with numerous issues of first impression in this complicated case, District Judge Gerald McHugh, sitting by designation, handled this case with exceptional precision and care. We will affirm the District Court in all respects. II. Facts and Procedural History David Matusiewicz and Christine Belford were married from 2001 to 2006, during which time they had three children, L.M.1, L.M.2, and K.M.1 (the "children"). The couple and their children also lived with Belford's one child from a previous marriage, K.M.2. After their divorce, Belford and David engaged in a bitter custody dispute, during which David accused Belford of being an unfit mother and suffering from mental health disorders. On February 13, 2007, following an evaluation by a psychologist who determined that David's allegations were unfounded, the Delaware Family Court awarded joint custody of the children. On August 26, 2007, rather than let the children return from staying with David to live with Belford, David, along with his mother Lenore, kidnapped L.M.1, L.M.2, and K.M.1 and absconded to Central America. During the kidnapping, David told L.M.1 that Belford had committed suicide. In March 2009, the children were located in Nicaragua and rescued, and David and Lenore were arrested. The children returned to live with Belford, who had been awarded sole custody during the kidnapping. David pleaded guilty to federal kidnapping charges and was sentenced to 48 months of imprisonment on December 10, 2009. Appendix ("App.") 137. Later that month, while incarcerated, David sent a letter to his sister, Amy Gonzalez, in which he stated, "I'm done playing Mr. Nice Guy," and urged her to "begin making complaints anonymously and repeatedly to [Delaware Youth and Family Services]." App. 3389-90, 7222. He also instructed her to "make sure Melinda's website is up and has a true story on it and is well publicized." App. 3390, 7222. Beginning in December 2009, a webpage was published that identified Belford and her children by name and set forth detailed claims against Belford of sexual abuse, physical abuse, and neglect of the children. That website was registered to Melinda Kula, the sister-in-law of Thomas and Lenore. It stated that the "[a]ctual names were used by the request and with the permission of David Matusiewicz." App. 7882. In March and April 2011, Gonzalez published three YouTube videos, which included secret recordings of Belford and the children taken by a private investigator; posts claiming Belford sexually abused her daughter, L.M.1; and images of polygraph test results of Lenore and Gonzalez, which described the accusations of sexual abuse. From May 2011 through September 2012, David and Gonzalez had contact with David's former girlfriend, Cindy Bender, and enlisted her to probe Belford for details about her life and to share what she learned, which included information from Belford's private Facebook account. Acting on instructions received from David while he was in prison, Lenore and Gonzalez mailed letters that accused Belford of sexual abuse to numerous media outlets, to the children's school and teachers, and to Belford's family members, neighbors, employer, church, and other members of her community. The defendants also mailed letters and cards directly to Belford and her children. Gonzalez and Thomas solicited their friends to drive past Belford's home and report on what they observed. The defendants also convinced a real estate agent in Delaware to conduct surveillance of Belford's house and to provide them with information about Belford's residence and about various persons who were part of Belford's life and who were coming and going from her home. Between November 2010 and July 2011, the Delaware Family Court conducted a hearing over seven separate days on Belford's petition for termination of David's parental rights as to the children. On August 18, 2011, the Delaware Family Court entered an order terminating David's parental rights as well as Thomas's, Lenore's, and Gonzalez's familial rights (the "TPR Order"). App. 7827-68, 4310. The Delaware Supreme Court affirmed that decision. App. 2154-55. In spite of the TPR Order, the defendants continued to send letters to Belford's home and made extrajudicial contact with the lawyers, judges, and witnesses involved in the TPR matter. Thomas and Lenore made numerous phone calls to the chambers of the judge overseeing a separate civil matter between Belford and the Matusiewicz family, during which they told the judge's assistant, referring to Belford, that the "bitch is going to get what is coming to her." App. 3057. On December 1, 2011, Thomas and Lenore travelled to Delaware and showed up uninvited at Belford's house. Although Belford was not at home, the children and Belford's boyfriend were. Belford's boyfriend instructed Thomas to leave. This trip was ostensibly to visit the children, despite the fact that Delaware Family Court had previously denied petitions by both Thomas and Gonzalez to visit the children. The night before the trip, Thomas and Gonzalez exchanged emails in which Thomas informed Gonzalez of the visit, instructed her to clean out his home safe, and told her that he would let her know how things worked out. App. 3319-21, 8886. In response, Gonzalez gave Thomas her temporary cell phone number and told him to be careful. App. 8886. In the emails, Thomas and David refer to Belford by a nickname, "wb," which stood for "Whore Bitch." App. 3243-44. Thomas sent a letter to David after his visit that contained the details of what he had observed. App. 7226-28. After this visit, Belford took steps to sell her home and move. The defendants then obtained the real estate listing - before it was made publicly available - from the real estate agent whom they had enlisted to surveil Belford. On November 1, 2012, David sent Gonzalez an email saying, "[p]repare yourself to be managing four by this time in 2013." App. 3460-61. Gonzalez responded to the email by stating that she was "praying for it." App. 3462. The Government's case agent later testified that the reference to "four" equated to David's three children plus Gonzalez's one child. App. 3461. On November 5, 2012, David filed a petition to reduce his back payments of child support in Delaware Family Court. A hearing was scheduled in Delaware, and although David was informed he could participate by phone as he resided with his family in Texas at the time, he chose to attend in person. David received permission from his probation officers to attend, but he failed to disclose to them that he could participate by phone or that his parents would be accompanying him. On February 4, 2013, David, Lenore, and Thomas drove to Delaware in two vehicles, which were loaded with an assault rifle, handguns, military-style knives, thousands of rounds of ammunition, restraints, body armor, binoculars, an electric shock device, gas cans, a shovel, photographs of Belford's children and residence, and handwritten notes about Belford's neighbors. Thomas left a note for Gonzalez in a hutch in the family's residence, instructing her to keep his guns for protection and that stated "hopefully we can end this BS now - up to Dave." App. 3318, 7461. On February 11, 2013, Thomas and David entered the New Castle County Courthouse lobby, in Delaware, and remained there for approximately 25 to 30 minutes, during which time David and Thomas exchanged envelopes, before David passed through the security checkpoint. Belford entered the courthouse with her friend Laura "Beth" Mulford a short time later. Thomas then shot and killed both women, injured two police officers in an exchange of fire, and then shot himself in the head. Investigators recovered from Thomas's person two death certificates that were filled out with the names of Belford and her family court attorney. Investigators also found papers containing Thomas's burial request during a search of David's person following his arrest. On February 13, 2013 - two days later - Gonzalez submitted a petition for custody of the children to the Delaware Family Court in the New Castle County Courthouse, with a check dated February 12, 2013. App. 4306-07. The petition was denied. In the ensuing six months, Gonzalez continued to file additional custody petitions. App. 4307-12, 7974-8009. Gonzales also made repeated attempts to contact the children through the mail. App. 4312-13, 8542-45. On August 6, 2013, David Matusiewicz, Lenore Matusiewicz, and Amy Gonzalez were indicted on the following counts: (1) conspiracy to commit interstate stalking and cyberstalking, in violation of 18 U.S.C. §§ 2261A(1) and (2), all in violation of 18 U.S.C. § 371 ; (2) interstate stalking in violation of 18 U.S.C. §§ 2261A(1), 2261(b) and 2; (3) interstate stalking resulting in the death of Belford, in violation of 18 U.S.C. §§ 2261A(1), 2261(b) and 2; and (4) cyberstalking resulting in the death of Belford, in violation of 18 U.S.C. §§ 2261A(2), 2261(b) and 2. Counts One and Four were against all defendants. Count Two was only against Lenore. Count Three was against David and Lenore. Thomas was listed as an unindicted co-conspirator in the indictment. All three defendants pleaded not guilty, and the case proceeded to trial. We set forth a brief summary of the evidence introduced by the Government at trial relevant to the issues on appeal. This includes evidence that after the shooting, law enforcement officers found firearms and ammunition in the vehicles that the Matusiewicz family had driven from Texas. The key to this vehicle was found on David's person. The Government also introduced evidence of a surveillance video from a Walmart parking lot in Maryland that depicted Thomas, David, and Lenore walking around the vehicle with its trunk open, demonstrating that all three knew of the weapons and ammunition. Law enforcement recovered a red notebook entitled "Important Information for David Matusiewicz" from the vehicle that David and Thomas drove to the courthouse; the contents of this notebook were in Thomas's handwriting. App. 3224-35. Within were the real estate listing for and pictures of Belford's home, accompanied by handwritten notes identifying the bedrooms in which Belford and her children slept. It also contained personal, identifying information on Belford's family, lawyers, doctors, boyfriend, and employer, as well as a daily surveillance log tracking Belford's movements over a twelve-day period in March 2010. Additionally, there was a page marked "HL," which the Government argued stood for "hit list," that identified sixteen individuals, including the judges, lawyers, and witnesses involved in the prior federal kidnapping and family court cases. App. 3249-53, 5442, 6995. The Government introduced evidence recovered from a search of Gonzalez's residence. This included large volumes of correspondence with third parties about the stalking campaign. It also introduced letters from Thomas to Gonzalez that they "must drink to WB's, [a nickname for Belford,] final day," that Belford "can not keep" the children "at all costs," and that Belford "can not [and] will not have our girls into her old age. Ain't gonna happen." App. 3442-43. At trial, a key part of the Government's case was that the defendants' accusations that Belford sexually molested her children and suffered from mental health disorders were false and defamatory. The spreading of these false claims was an important part of the defendants' campaign to harass and intimidate Belford. The Government provided ample evidence demonstrating the falsity of these claims. Notably, L.M.1 testified that her mother did not abuse her, and refuted the specific claimed incidents of abuse advanced by the defendants. L.M.1 also testified that she was afraid when she learned of the allegations and saw her name and personal information online. The Government also provided the testimony of L.M.1's pediatrician and psychologist who corroborated that L.M.1 never reported nor showed any signs of abuse. The Government also discredited the defendants' accusations of abuse by pointing out that the timeline of their claims of abuse did not add up. No accusations of sexual abuse were made prior to the kidnapping in August 2007. Evidence was introduced that at his TPR hearing, David testified that he kidnapped the children upon learning about the abuse in either July or August 2007. However, evidence also showed that David began preparing for the kidnapping as early as fall 2006. The Government introduced evidence that defendants gave contradictory and shifting statements about when and how they learned of the abuse, and about the details of the incidents of abuse. The Director of the Delaware Division of Family Services ("DDFS"), the state organization responsible for investigation of child abuse, also testified, explaining that DDFS did not open an investigation into the abuse because it found that the defendants' contradictory claims lacked credibility. Belford's eldest child, K.M.2, testified that she, her mother, and her siblings were aware of the defendants' conduct and it caused them to fear for their lives. L.M.1 also testified about her fear, and the pain of losing her mother. The Government also produced evidence from numerous third parties to whom Belford had confided her own fears of the defendants, resulting from their conduct. For example, Belford's therapist testified as to the emotional and psychological toll that the defendants' actions were having on Belford. After a five week trial, the jury convicted the defendants on all counts. On February 18, 2016, the District Court held a sentencing hearing. The District Court applied a number of sentencing enhancements, including: (1) the first-degree murder cross-reference pursuant to United States Sentencing Guidelines ("U.S.S.G.") § 2A1.1 ; (2) the vulnerable victim enhancement pursuant to U.S.S.G. § 3A1.1(b)(1) ; and (3) the official victim enhancement pursuant to U.S.S.G. § 3A1.2(c)(1). App. 6057-6126. The District Court sentenced each of the defendants to a term of five years of imprisonment on Count One, and a term of life imprisonment for Count Four. App. 2-8, 10-15. This timely appeal followed. III. Analysis The defendants raise numerous challenges to their convictions and sentences. David brings challenges to: (1) the sufficiency of the evidence; (2) the lack of a specific unanimity instruction; (3) the District Court's "death resulted" instruction; (4) the District Court's alleged judicial factfinding in violation of Apprendi v. New Jersey, 530 U.S. 466, 120 S.Ct. 2348, 147 L.Ed.2d 435 (2000), in imposing the sentence; (5) the application of the vulnerable victim and official victim sentencing enhancements; (6) the admission of the TPR Order into evidence; (7) the admission of Belford's past therapy sessions and emails into evidence; and (8) the testimony of the FBI case agent vouching for the weight of the case. In addition to joining these challenges, Gonzalez also raises the following additional issues: (9) that the anti-cyberstalking statute violates the First Amendment and is void for vagueness; (10) that the District Court lacked jurisdiction to sit in the District of Delaware because venue was transferred out of Delaware; (11) that her polygraph evidence offered in rebuttal was erroneously excluded; (12) that the District Court erred in ruling that Government would be permitted to cross-examine any character witnesses about her prior conduct in relation to the kidnapping; and (13) that her sentence of life imprisonment violates the Eighth Amendment. We will address each of these issues in turn. A. Sufficiency of the Evidence Challenge "We apply a 'particularly deferential' standard of review to a challenge to the sufficiency of evidence supporting a jury verdict." United States v. Peppers, 302 F.3d 120, 125 (3d Cir. 2002) (quoting United States v. Cothran, 286 F.3d 173, 175 (3d Cir. 2002) ). Under this standard, we will affirm the verdict if " 'any rational juror' could have found the challenged elements beyond a reasonable doubt, viewing the evidence in the manner that is most favorable to the government, neither reweighing evidence, nor making an independent determination as to witnesses' credibility." Id. (quoting Cothran, 286 F.3d at 175 ). Count One charged the defendants with conspiring to commit interstate stalking and cyberstalking, in violation of 18 U.S.C. § 371. To establish a conspiracy under this section, the Government must prove: (1) an agreement between two or more persons to commit the substantive offense; (2) that each defendant knowingly joined the conspiracy; and (3) an overt act committed by one of the conspirators in furtherance of the conspiracy. See United States v. Gebbie, 294 F.3d 540, 544 (3d Cir. 2002). This requires proof that a defendant has "knowledge of the conspiracy's specific objective." United States v. Caraballo-Rodriguez, 726 F.3d 418, 431 (3d Cir. 2013) (en banc). We have held that "a conspiratorial agreement can be proven circumstantially based upon reasonable inferences drawn from actions and statements of the conspirators or from the circumstances surrounding the scheme." United States v. McKee, 506 F.3d 225, 238 (3d Cir. 2007). Count Three charged only David and Lenore with interstate stalking, in violation of 18 U.S.C. § 2261A(1). To prove interstate stalking, the Government was required to prove that David: [ (1) ] travel[ed] in interstate or foreign commerce ... [ (2) ] with the intent to kill, injure, harass, intimidate, or place under surveillance with intent to kill, injure, harass, or intimidate another person, and [ (3) ] in the course of, or as a result of, such travel ... engage[d] in conduct that-- (A) place[d] that person in reasonable fear of the death of, or serious bodily injury to- (i) that person; (ii) an immediate family member ... of that person; or (iii) a spouse or intimate partner of that person; or (B) cause[d], attempt[ed] to cause, or would be reasonably expected to cause substantial emotional distress [to that person or their spouse, intimate partner, or immediate family member]. 18 U.S.C. § 2261A(1). Count Four, brought against all of the defendants, charged cyberstalking resulting in the death of Belford, in violation of 18 U.S.C. §§ 2261A(2), 2261(b), and 2. We have held that to prove stalking under 18 U.S.C. § 2261A(2), the Government must establish that (1) the defendants used a facility of interstate commerce; (2) to engage in a course of conduct that places a person in reasonable fear of death or serious bodily injury, or causes substantial emotional distress, either to that person or to a partner or immediate family member; (3) "with the intent to kill, injure, harass, intimidate, or place under surveillance with intent to kill, injure, harass, or intimidate that person." 18 U.S.C. § 2261A(2) ; see also United States v. Fullmer, 584 F.3d 132, 163 (3d Cir. 2009). The statute defines a "course of conduct" as "a pattern of conduct composed of 2 or more acts, evidencing a continuity of purpose." 18 U.S.C. § 2266. A defendant who violates § 2261A is eligible for a sentence of life imprisonment if the "death of the victim results." Id. § 2261(b)(1). The defendants each argue that the evidence presented to the jury was insufficient to convict them of any of the counts in the indictment. Their sufficiency challenges revolve around the same argument that was presented to and rejected by the jury: that Thomas acted alone in killing Belford and the defendants neither knew about nor participated in his plan. The defendants argue that there is insufficient evidence of a conspiracy because there was no evidence of an express agreement to stalk or kill Belford. They do not dispute the existence of their campaign to spread accusations that Belford sexually abused the children, but contend that it was not a stalking campaign because it was meant to spur an investigation of these claims, which the defendants purport to have sincerely believed. However, the jury was presented with overwhelming evidence demonstrating both that the sexual abuse accusations against Belford were false and that defendants knew that these allegations were false. We have reviewed the substantial amount of evidence before the jury. Taken in the light most favorable to the Government, see Peppers, 302 F.3d at 125, the evidence is more than sufficient to support the jury's verdict in its entirety. Throughout the course of the five-week trial, the Government produced approximately 65 witnesses and over 760 exhibits, which show that the defendants conspired to engage in an escalating campaign of harassment, intimidation, and surveillance against Belford, all with the goal of regaining custody of the children. This three-year stalking campaign culminated in the murder of Belford in the New Castle County Courthouse lobby by Thomas, a member of the conspiracy. Both David and Gonzalez were intimately involved in this stalking campaign and conspiracy. The evidence demonstrating David's involvement included: directing his family to send letters to Belford's acquaintances accusing Belford of sexual abuse; setting up the in-person court hearing that brought Belford to the courthouse where Thomas shot her; lying to probation officers about the need to attend the hearing in person; and traveling from Texas to Delaware in two vehicles that were filled with numerous weapons. The evidence demonstrating Gonzalez's involvement included: spreading the false accusations of child abuse by creating online postings and YouTube videos, and sending defamatory emails and letters to Belford's acquaintances; preparing false polygraph reports about these accusations; recruiting third parties to surveil and report on Belford and the children; providing Thomas with her temporary cell phone number and cleaning out his safe when he traveled to Delaware in 2011 and showed up at Belford's house; and filing numerous petitions for custody of the children beginning two days after Belford was killed. Thus, we conclude that the evidence was more than sufficient to support the conspiracy charges against David and Gonzalez. As to the charged violation of § 2261A(2), the Government produced sufficient evidence that David and Gonzalez committed cyberstalking that resulted in Belford's death. Our review of the record demonstrates that the evidence shows that each of the defendants engaged in many more than the two requisite acts in furtherance of their long campaign to defame and accuse Belford of sexual abuse of her children. The purpose of this campaign, and the acts committed in furtherance thereof, was to regain custody of the children by removing Belford - or causing her to remove herself - from the equation. The evidence discussed above was more than sufficient for the jury to determine that the accusations against Belford were false, and thus infer that the defendants continued making these accusations with the intent to harass or intimidate Belford. The record also contains overwhelming evidence of the fear and emotional distress suffered by Belford and her children. This includes testimony by Belford's children about their awareness and fear of the defendants' conduct. The Government also produced evidence from numerous third parties to whom Belford had confided her fears of the defendants due to their conduct, including Belford's discussions with her therapist about the emotional and psychological toll that the defendants' actions had on her. Finally, the Government produced sufficient evidence to prove that the defendants' conduct resulted in Belford's death, thus making them eligible for life sentences under § 2261(b)(1). As discussed more thoroughly below with regard to the jury instruction challenge, the District Court properly instructed the jury that the defendants could be responsible for Belford's death either because their actions were the actual and proximate cause of her death, or by way of co-conspirator liability, if she was killed by a co-conspirator acting in furtherance of the conspiracy. Our review of the record demonstrates that there is sufficient evidence to establish either theory of liability. David's involvement in the stalking campaign, as well as his actions in setting up the court hearing and bringing Thomas to the courthouse where he then shot Belford, are sufficient to support an interference that he was the "but for" cause of Belford's death. And as discussed above, there is sufficient evidence to support the inference that he had the specific intent that Belford should die. See supra, note 7. As to Gonzalez, her involvement in the stalking campaign also demonstrates that she was a "but for" cause of Belford's death. Gonzalez's numerous communications with her family members indicate that it was reasonably foreseeable to her that Belford's murder at her family's hands might soon come to pass, and support an inference that she was the proximate cause of Belford's death. This evidence includes the correspondence from Thomas to Gonzales that the two drink to Belford's "final day" and the communication from David that Gonzalez should prepare herself to soon be managing four children. Further, Gonzalez was ready to - and did - petition for custody of the children almost immediately after Belford was killed. For the foregoing reasons, the evidence produced at trial was more than sufficient to support the jury's verdict. B. Jury Instruction Challenges The defendants raise two challenges to the District Court's jury instructions. They contend that the District Court (1) erred in not providing a specific unanimity instruction, and (2) erred in its construction of the "death results" instruction. Our "[r]eview of the legal standard enunciated in a jury instruction is plenary, but review of the wording of the instruction, i.e., the expression, is for abuse of discretion." United States v. Yeaman, 194 F.3d 442, 452 (3d Cir. 1999) (citation omitted). Because the defendants failed to object to the unanimity instructions or raise the specific unanimity instruction issue before the District Court, we review that issue for plain error. See United States v. Poulson, 871 F.3d 261, 270 (3d Cir. 2017). Under plain error review, we require the defendants to show that there is: (1) an error; (2) that is "clear or obvious;" and (3) that "affected the appellants' substantial rights." United States v. Stinson, 734 F.3d 180, 184 (3d Cir. 2013) (citations omitted). "If those three prongs are satisfied, we have 'the discretion to remedy the error - discretion which ought to be exercised only if the error seriously affect[s] the fairness, integrity, or public reputation of judicial proceedings.' " Id. (quoting Puckett v. United States, 556 U.S. 129, 135, 129 S.Ct. 1423, 173 L.Ed.2d 266 (2009) ). 1. Lack of a Specific Unanimity Instruction The defendants argue that the District Court erred because it failed to give a specific unanimity instruction to inform the jury that it must unanimously agree on which specific acts the defendants committed. To prove cyberstalking under 18 U.S.C. § 2261A(2), the Government must, inter alia, establish that the defendant engaged in a course of conduct that placed a person in reasonable fear of death or serious bodily injury, or causes substantial emotional distress, either to that person or to a partner or immediate family member, "with the intent to kill, injure, harass, intimidate, or place under surveillance with intent to kill, injure, harass, or intimidate" that person. 18 U.S.C. § 2261A(2) ; Fullmer, 584 F.3d at 163. The defendants argue that the jury was required to be unanimous on which of the specific acts it found to be part of the defendants' course of conduct. "It is well settled that a defendant in a federal criminal trial has a constitutional right to a unanimous verdict." Yeaman, 194 F.3d at 453. We have acknowledged that "[t]his includes the right to have the jury instructed that in order to convict, it must reach unanimous agreement on each element of the offense charged." Id. This is known as the "general unanimity instruction." United States v. Beros, 833 F.2d 455, 460 (3d Cir. 1987). Typically, when an indictment alleges a number of different factual bases for the defendants' criminal liability, the general unanimity instruction ensures that the jury unanimously agrees on the factual basis for a conviction. Id. However, "this does not mean one has a right to insist on an instruction requiring unanimous agreement on the means by which each element is satisfied." Yeaman, 194 F.3d at 453. In the case where "a statute enumerates alternative routes for its violation, it may be less clear ... whether these are mere means of committing a single offense (for which unanimity is not required) or whether these are independent elements of the crime (for which unanimity is required)." Id. Here, the defendants contend that specific unanimity is required because the statute contains multiple alternative routes for its violations, which consist of distinct elements. In their briefing, the defendants identify two different portions of the statute which they argue consist of distinct elements requiring specific unanimity: (1) the two specific acts that must be proven to establish the course of conduct requirement, and (2) the mens rea requirement. The Government contends that these are no more than distinct means of committing cyberstalking, not elements. The defendants argue in the alternative that the uncertainty over whether these are elements or means creates the potential for jury confusion, which would also necessitate a more specific unanimity instruction. See Beros, 833 F.2d at 460 (observing that the general unanimity instruction can be insufficient "where the complexity of the case, or other factors, creates the potential that the jury will be confused"). The defendants thus contend that under Beros, the District Court was required to provide a more specific unanimity instruction. We disagree. In Beros, we described a scenario in which the general unanimity instruction is not sufficient, concluding that When it appears ... that there is a genuine possibility of jury confusion or that a conviction may occur as the result of different jurors concluding that the defendant committed different acts, the general unanimity instruction does not suffice. To correct any potential confusion in such a case, the trial judge must augment the general instruction to ensure the jury understands its duty to unanimously agree to a particular set of facts. Id. at 461 (alteration in original) (emphasis omitted) (quoting United States v. Echeverry, 698 F.2d 375 (9th Cir.), modified, 719 F.2d 974, 975 (9th Cir. 1983) (en banc) ). The indictment at issue in Beros advanced multiple different theories for how the defendant had violated the relevant statute. Id. at 460. There, the Government charged the defendant under a disjunctively worded statute, alleging that the defendant violated that statute by engaging in three separate and different acts. Id. We held that the district court abused its discretion in not specifically instructing the jury that it had to be unanimous as to at least one of the three acts committed. Id. at 460-63. We determined that "[w]hen the government chooses to prosecute under an indictment advancing multiple theories, it must prove beyond a reasonable doubt at least one of the theories to the satisfaction of the entire jury." Id. at 462. We went on to specify that the Government "cannot rely on a composite theory of guilt, producing twelve jurors who unanimously thought the defendant was guilty but who were not unanimous in their assessment of which act supported the verdict." Id. Since Beros, we have reiterated that "the need for a specific unanimity instruction is the exception to the 'routine case' in which a 'general unanimity instruction will ensure that the jury is unanimous on the factual basis for a conviction, even where an indictment alleges numerous factual bases for criminal liability.' " United States v. Cusumano, 943 F.2d 305, 312 (3d Cir. 1991) (quoting Beros, 833 F.2d at 460 ). And, we have held that "[t]he Beros rule comes into play only when the circumstances are such that the jury is likely to be confused as to whether it is required to be unanimous on an essential element." Id. Thus, Beros applies where the Government advances different factual theories concerning the defendants' charged conduct, each of which could independently satisfy the elements of the crime. In such a situation, a specific unanimity instruction is needed to ensure that the jury agrees on which of a (or a set of) charged act(s) that the defendant committed constituted criminal behavior. For example, in Beros, the indictment alleged that defendant embezzled money from a pension fund of which he was a trustee. Beros, 833 F.2d at 458. One count of the indictment alleged three separate transactions of [his] criminal conduct: (1) the use of a Joint Council credit card to pay air fare for himself and his wife; (2) occupying a hotel suite that cost $160.00 per day rather than a single or double room which would cost no more than $60.00 per day; and (3) remaining in Florida for a couple of additional days for personal reasons after the conclusion of the conference. Id. at 461. We held that a specific unanimity instruction was needed to ensure that the jury did not return a guilty verdict where all jurors agreed that the defendant engaged in criminal conduct, but some jurors thought that only the first transaction constituted criminal conduct, and others thought that only the second or third transactions constituted criminal conduct. Id. We reasoned that in such a scenario, "the jury would unanimously conclude that there was a mode or manner of violating the law, but there would be no unanimity as to the predicate act. Also, under such a scenario, any verdict would be defective because of the lack of real unanimity." Id. at 462. In contrast, we have held that a specific unanimity instruction is not needed, because the same potential for juror confusion does not exist, where "the government did not allege different sets of facts, and the only possible confusion arose from the disjunctive nature of the charge under the statute." Cusumano, 943 F.2d at 312. Applying Beros, we have since observed that "[w]e have never required that jurors be in complete agreement as to the collateral or underlying facts which relate to the manner in which the culpable conduct was undertaken." United States v. Jackson, 879 F.2d 85, 88 (3d Cir. 1989). We hold that the District Court was not required to issue a specific unanimity instruction in this case. Neither the mens rea requirements of § 2261A(2) nor the individual acts which constituted the statute's "course of conduct" requirement constitute distinct elements of the offense. As to the mens rea requirement, we have held that different mental states in a statute constitute alternate means and not alternate elements. See United States v. Navarro, 145 F.3d 580, 586 (3d Cir. 1998). In Navarro, we determined that "it is neither clear nor obvious that the three alternative mental states defined in § 1956[, the anti-money-laundering statute,] could not properly be treated as separate means of committing a single offense." Id. at 592. This conclusion followed from the Supreme Court's decision in Schad v. Arizona, 501 U.S. 624, 111 S.Ct. 2491, 115 L.Ed.2d 555 (1991), which held that a specific unanimity instruction was not needed for a prosecution under "an Arizona statute which defined first-degree murder as being either (a) willful, deliberate, or premeditated, or (b) committed in the course of certain felonies," because those two alternatives were not separate elements but instead "alternative means of satisfying an element of an offense." Navarro, 145 F.3d at 586 (citing Schad, 501 U.S. at 628, 111 S.Ct. 2491 ). Here, the statute requires that the defendant act "with the intent to kill, injure, harass, intimidate, or place under surveillance with intent to kill, injure, harass, or intimidate." 18 U.S.C. § 2261A(2). Nothing in the text of the statute or any cases interpreting it indicates that it was intended to create separate offenses for stalking "with the intent to kill" as opposed to stalking "with the intent to ... injure" or "with the intent to ... harass." Instead, the statute requires that the defendant engage in "a pattern of conduct composed of 2 or more acts, evidencing a continuity of purpose" that "places that person in reasonable fear of the death of or serious bodily injury" or causes that person "substantial emotional distress." Id. §§ 2261A(2), 2266. A defendant violates the statute if that conduct is engaged in with one of the aforementioned mentes reae. We have noted that "different means for committing an offense 'must reflect notions of equivalent blameworthiness or culpability.' " Yeaman, 194 F.3d at 454 n.6 (quoting UnitedStates v. Edmonds, 80 F.3d 810, 820 (3d Cir. 1996) ). The offense here stresses the effect that the defendant's conduct has on the victim. Thus, as long as that conduct was taken with an intent to cause the victim harm, the specific mental state does not make a difference to the defendant's culpability. This is evidenced by the fact that the statute sets forth different tiers of punishment based not on the mental state of the defendant, but on the harm suffered by the victim. See 18 U.S.C. § 2261(b). The decisions of our sister Courts of Appeals interpreting § 2261A(2) support our view that the mens rea requirement constitutes alternate means as opposed to alternate elements of the offense. The Court of Appeals for the Fourth Circuit, for instance, has declined to parse the different mentes reae, and observed that "[i]t is an element of the crime that [the defendant] have intended harm to a particular victim." UnitedStates v. Shrader, 675 F.3d 300, 311 (4th Cir. 2012). The Court of Appeals for the Ninth Circuit has also treated the mens rea requirement as a single element in conducting its analysis of the statute. See United States v. Osinger, 753 F.3d 939, 947 (9th Cir. 2014). A specific unanimity instruction was also not needed as to the course of conduct requirement. The jury is not required to agree on which specific acts were part of the stalking campaign. The statute defines the required "course of conduct" as "a pattern of conduct composed of 2 or more acts, evidencing a continuity of purpose." 18 U.S.C. § 2266(2). The defendants argue that because, to be convicted of cyberstalking, they must have committed two or more acts as part of the course of conduct, the jury needs to agree on the specifics of which acts were committed with the requisite criminal intent. However, the two or more specific acts that constitute a course of conduct are not distinct elements of the offense. The crux of the course of conduct requirement is that the defendants have engaged in "a pattern of conduct," which "evidenc[es] a continuity of purpose." Id. § 2266(2). This language is significant. The focus is not on the individual acts as separate, distinct events, but instead on the purpose and scope of the defendants' pattern of stalking conduct as a whole. See UnitedStates v. Conlan, 786 F.3d 380, 386 (5th Cir. 2015) ("[T]he statute's intent requirement 'modifies the cumulative course of conduct as a whole,' " and avoids criminalizing otherwise innocent acts) (quoting Shrader, 675 F.3d at 311-12 ). Nothing in the statute requires that the individual acts be criminal violations on their own. The statute does not require that a defendant commit multiple criminal acts to engage in a course of conduct. Instead, it is the pattern of conduct formed by the individual acts, undertaken with a continuity of purpose, that constitutes the criminal violation. As the Court of Appeals for the Fourth Circuit observed, While the statute does not impose a requirement that the government prove that each act was intended in isolation to cause serious distress or fear of bodily injury to the victim, the government is required to show that the totality of the defendant's conduct "evidenc[ed] a continuity of purpose" to achieve the criminal end. Shrader, 675 F.3d at 311. The court then concluded that "[t]his statutory scheme reflects a clear understanding on the part of Congress that while severe emotional distress can of course be the result of discrete traumatic acts, the persistent efforts of a disturbed harasser over a period of time ... can be equally or even more injurious." Id. at 311-12. As a result, "[t]he cumulative effect of a course of stalking conduct may be greater than the sum of its individual parts." Id. at 312. The court thus rejected the intent and unanimity position that the defendants take here, because it held "[t]o read in a requirement that each act have its own specific intent element would undo the law's protection for victims whose anguish is the result of persistent or repetitive conduct on the part of a harasser." Id. For the foregoing reasons, the District Court's failure to include a specific unanimity instructions was not an error, and the defendants are not entitled to relief under plain error review. 2. "Death Results" Instruction The defendants next argue that the District Court erred in its construction of the special instruction it gave the jury to determine whether the defendants qualified for the "death of the victim results" sentencing enhancement. 18 U.S.C. § 2261(b)(1). The proper construction of this instruction was an issue of first impression for the District Court and remains one for us. The defendants concede that this instruction should be reviewed for plain error. Matusiewicz Br. 66, 75. The District Court gave the following "death results" instruction as part of its "Special Interrogatory Regarding the Death of Christine Belford - Counts Three and Four" jury instruction: A person's death "results" from an offense only if that offense caused, or brought about, that death. In determining whether the particular offenses charged in Counts 3 or 4 caused Christine Belford's death, you must affirmatively answer two questions. First, would Christine Belford's death have occurred as alleged in the Indictment in the absence of the particular offense? Stated differently, you should decide whether Ms. Belford would have died at the New Castle County Courthouse on February 11, 2013, but for the particular offense. Second, was Christine Belford's death the result of the particular offense in a real and meaningful way? This includes your consideration of whether her death was a reasonably foreseeable result of the particular offense and whether her death could be expected to follow as a natural consequence of the particular offense. With regard to the special interrogatories for Counts Three and Four, if you found the Defendant guilty of conspiracy under Count One it is not necessary for you to find that a particular defendant's personal actions resulted in the death of Christine Belford. A defendant may be held accountable for the death of Christine Belford based on the legal rule that each member of a specific conspiracy is responsible for acts committed by the other members, as long as those acts were committed to help further or achieve the objective of the specific conspiracy and were reasonably foreseeable to the defendant as a necessary or natural consequence of the agreement. In other words, under certain circumstances the act of one conspirator may be treated as the act of all. This means that all the conspirators may be held accountable for acts committed by any one or more of them, even though they did not all personally participate in that act themselves. In order for you to answer "yes" to the jury interrogatories for Counts Three or Four based upon this legal rule, you must find that the Government proved beyond a reasonable doubt each of the following four (4) requirements with regard to the charge at issue: First: That the defendant was a member of the conspiracy to commit the particular offense charged in Count One of the Indictment; Second: That while the defendant was still a member of the conspiracy, one or more of the other members of the same conspiracy also committed the offense charged in Count Three or Count Four, by committing each of the elements of that offense as I explained those elements to you in these instructions, and his or her acts therein resulted in the death of Christine Belford according to the instructions I have just given you. However, the other member of the conspiracy need not have been found guilty of (or even charged with) the offense in question, as long as you find that the Government proved beyond a reasonable doubt that the other member committed the offense. Third: That the other member of the conspiracy committed this particular offense within the scope of the unlawful agreement and to help further or achieve the objectives of the specific conspiracy; and Fourth: That Ms. Belford's death was reasonably foreseeable to or reasonably anticipated by the defendant as a necessary or natural consequence of the unlawful agreement. The Government does not have to prove that the defendant specifically agreed or knew that Ms. Belford's death would result. However, the Government must prove that Ms. Belford's death was reasonably foreseeable to the defendant, as a member of the conspiracy, and within the scope of the agreement as the defendant understood it. App. 5871-72. The defendants contend that the District Court erred by giving this instruction. They contend that the instruction should have required that the jury find that there was an agreement among the defendants to cause Belford's death. They also contend that under the instructions the District Court gave, the jury could not have found that the defendants caused Belford's death. The Government argues that this instruction properly set forth the two possible ways that the jury could find that the defendants' actions resulted in Belford's death. These theories of liability are that: (1) Belford's death resulted from the defendants' personal actions if the defendants' personal actions were the actual and proximate cause of Belford's death, or (2) the defendants are responsible for Belford's death under co-conspirator liability. The District Court included both theories in its jury instruction and clearly distinguished between them. With respect to the first theory, that the defendants' personal actions were the actual and proximate cause of Belford's death, the District Court observed that its instruction held the jury to a higher standard than it believed the law required. See App. 61. Under this theory, the instruction required that the jurors find that each defendant's conduct was the actual cause of Belford's death and, in the context of the proximate cause question, that the death was "the result of the particular offense in a real and meaningful way," including whether it was "reasonably foreseeable" and "could be expected to follow as a natural consequence of the particular offense." App. 5871. The District Court observed that it included this language "to increase the government's burden by highlighting for the jury the need for there to exist a genuine nexus between the Defendants' conduct and the victim's death." App. 61. It explained that it required this heightened burden as to proximate cause, beyond what would be typically required for a proximate cause finding in tort law, as a "necessary safeguard" for the defendants' rights. App. 61. Because the issue of how to define for the jury the proof required to establish that the defendants' conduct caused the victim's death, thus triggering the "death results" enhancement under § 2261(b)(1), is one of first impression, the District Court issued a supplemental opinion explaining its reasoning for fashioning the jury instruction the way it did. See App. 56-61. The District Court explained that it looked to the cases defining "death results" language in other statutes, namely Burrage v. United States, 571 U.S. 204, 134 S.Ct. 881, 187 L.Ed.2d 715 (2014) and Paroline v. United States, 572 U.S. 434, 134 S.Ct. 1710, 188 L.Ed.2d 714 (2014), to form the basis for its causation instruction to the jury. The District Court then explained why it viewed the proximate cause requirement as requiring a heightened standard of proof here compared to that required under general tort law. We hold that the District Court did not err in crafting the jury instruction for the "death results" enhancement. The District Court properly followed Burrage and Paroline. In Burrage, the Supreme Court held that a "death results" sentencing enhancement in the Controlled Substances Act "is an element that must be submitted to the jury and found beyond a reasonable doubt," because it "increased the minimum and maximum sentences to which [the defendant] was exposed." Burrage, 571 U.S. at 210, 134 S.Ct. 881. The Court noted that such language meant that "a defendant generally may not be convicted unless his conduct is 'both (1) the actual cause, and (2) the 'legal' cause (often called the 'proximate cause') of the result.' " Id. (quoting 1 W. LaFave, Substantive Criminal Law § 6.4(a), 464-66 (2d ed. 2003) ). The Court continued on to discuss the "actual cause" standard, determining that it "requires proof 'that the harm would not have occurred' in the absence of-that is, but for-the defendant's conduct." Id. at 211, 134 S.Ct. 881 (quoting Univ. of Tex. Sw. Med. Ctr. v. Nassar, 570 U.S. 338, 347-48, 133 S.Ct. 2517, 186 L.Ed.2d 503 (2013) ). The Court did not discuss the proximate cause requirement, because it held that the actual cause requirement had not been satisfied where there was "no evidence" that the conduct at issue "was an independently sufficient cause of ... death." Id. at 215, 134 S.Ct. 881. The Court did address in detail the concept of proximate cause in Paroline. It observed that "a requirement of proximate cause is more restrictive than a requirement of factual cause alone," and that "proximate cause forecloses liability in situations where the causal link between conduct and result is so attenuated that the so-called consequence is more akin to mere fortuity." 572 U.S. at 446, 448, 134 S.Ct. 1710. The Court struggled to define proximate cause, noting that it "defies easy summary" and "is 'a flexible concept.' " Id. at 444, 134 S.Ct. 1710 (quoting Bridge v. Phoenix Bond & Indem. Co., 553 U.S. 639, 654, 128 S.Ct. 2131, 170 L.Ed.2d 1012 (2008) ). It determined that "to say that one event was a proximate cause of another means that it was not just any cause, but one with a sufficient connection to the result." Id. The Court observed that the proximate cause analysis in criminal and tort law "is parallel in many instances." Id. In its discussion, the Court noted that proximate cause is typically explained "in terms of foreseeability or the scope of the risk created by the predicate conduct." Id. at 445, 134 S.Ct. 1710. We hold that the District Court did not erroneously configure the portion of the "death results" instruction as to the direct theory of liability. The "actual cause" part of the District Court's instruction appropriately tracks the "but for" causation requirement of Burrage. 571 U.S. at 211, 134 S.Ct. 881. And the District Court's instruction on proximate cause required even a more stringent finding than that discussed by the Supreme Court in Paroline. Not only did the District Court require that the jury find Belford's "death was a reasonably foreseeable result of the particular offense," as is traditionally considered the proximate cause requirement, but also the District Court went further, requiring that the death result from the offense "in a real and meaningful way" and as a "natural consequence." App. 5871. The defendants have pointed to no authority that such a standard is insufficient to satisfy the proximate cause requirement. Thus, if anything, the District Court's instruction on proximate cause provided more protection for the defendants' rights than necessary under Supreme Court precedent. Accordingly, it was certainly not plain error for the District Court to give this instruction. Additionally, the District Court also properly instructed the jury that they could find the defendants liable under an alternative, co-conspirator theory of liability. The District Court's instruction on when conspirators can be held liable for the actions of their co-conspirators was not plain error as it followed this Court's model jury instructions and precedent. See Third Circuit's Model Criminal Jury Instruction § 7.03 "Responsibility For Substantive Offenses Committed By Co-Conspirators ( Pinkerton Liability)." We have held that "a participant in a conspiracy is liable for the reasonably foreseeable acts of his coconspirators in furtherance of the conspiracy." United States v. Cross, 308 F.3d 308, 311 n.4 (3d Cir. 2002) (citing Pinkerton v. United States, 328 U.S. 640, 647, 66 S.Ct. 1180, 90 L.Ed. 1489 (1946) ). This is known as the Pinkerton theory of liability. This doctrine "permits the government to prove the guilt of one defendant through the acts of another committed within the scope of and in furtherance of a conspiracy of which the defendant was a member, provided the acts are reasonably foreseeable as a necessary or natural consequence of the conspiracy." United States v. Lopez, 271 F.3d 472, 480 (3d Cir. 2001). Accordingly, we hold that the District Court did not plainly err in following our precedent and model jury instructions when instructing the jury that it could rely on co-conspirator liability. C. Substantive Challenges to the Prosecution of the Case 1. First Amendment Gonzalez argues that the indictment should have been dismissed because it violated the First Amendment. She brings an as-applied challenge to the cyberstalking statute. David joins Gonzalez's First Amendment arguments, but does not provide any separate discussion for an as-applied challenge as to his conduct. We review constitutional claims de novo. Garcia v. Att'y Gen, 665 F.3d 496, 502 (3d Cir. 2011). Gonzalez argues that she cannot be convicted for violating § 2261A(2) because her conduct constituted protected speech under the First Amendment. She argues that her speech - which consisted of, inter alia, sending emails to her co-defendants, sending correspondence to Belford and her children, contacting third parties, posting polygraph results and videos with accompanying commentary - was protected because she was expressing her sincerely held belief about Belford. She contends that her speech about Belford constituted an opinion, and as such receives complete protection under the First Amendment. The Government argues that this statute does not violate the First Amendment because it prohibits conduct, and any speech included in its breadth falls into an exception that does not warrant First Amendment protection. The First Amendment "permit[s] restrictions upon the content of speech in a few limited areas." United States v. Stevens, 559 U.S. 460, 468, 130 S.Ct. 1577, 176 L.Ed.2d 435 (2010) (quoting R.A.V. v. City of St. Paul, 505 U.S. 377, 382-83, 112 S.Ct. 2538, 120 L.Ed.2d 305 (1992) ). The Supreme Court has identified certain "well-defined and narrowly limited classes of speech" that can be proscribed without implicating the First Amendment. Id. at 468-69, 130 S.Ct. 1577 (quoting Chaplinsky v. New Hampshire, 315 U.S. 568, 571-72, 62 S.Ct. 766, 86 L.Ed. 1031 (1942) ). Relevant here, these classes of speech include (1) "defamation" and (2) "speech integral to criminal conduct." Id. at 468, 130 S.Ct. 1577. As to the first class of speech, the Supreme Court has held that defamatory statements are not protected by the First Amendment, reasoning that "[r]esort to epithets or personal abuse is not in any proper sense communication of information or opinion safeguarded by the Constitution, and its punishment as a criminal act would raise no question under that instrument." Beauharnais v. Illinois, 343 U.S. 250, 257, 72 S.Ct. 725, 96 L.Ed. 919 (1952) (quoting Cantwell v. Connecticut, 310 U.S. 296, 309, 60 S.Ct. 900, 84 L.Ed. 1213 (1940) ). And while statements of personal opinion are protected under the First Amendment, see Gertz v. Robert Welch, Inc., 418 U.S. 323, 339-40, 94 S.Ct. 2997, 41 L.Ed.2d 789 (1974), "there is no constitutional value in false statements of fact," id. at 340, 94 S.Ct. 2997. False statements of fact are not protected because "[n]either the intentional lie nor the careless error materially advances society's interest in 'uninhibited, robust, and wide-open' debate on public issues." Id. (quoting N.Y. Times Co. v. Sullivan, 376 U.S. 254, 270, 84 S.Ct. 710, 11 L.Ed.2d 686 (1964) ). As to the second class of speech, the Supreme Court has long maintained that speech integral to engaging in criminal conduct does not warrant First Amendment protection. See Giboney v. Empire Storage & Ice Co., 336 U.S. 490, 498, 69 S.Ct. 684, 93 L.Ed. 834 (1949). Thus, "[s]pecific criminal acts are not protected speech even if speech is the means for their commission." Packingham v. North Carolina, --- U.S. ----, 137 S.Ct. 1730, 1737, 198 L.Ed.2d 273 (2017). In Giboney, the Court held that enjoining otherwise lawful picketing activities did not violate the First Amendment where the sole purpose of that picketing was to force a company to enter an unlawful agreement in violation of Missouri's criminal antitrust laws. 336 U.S. at 501-02, 69 S.Ct. 684. The Court reasoned that such a restraint was justified because the otherwise lawful expressive activity was done for "the sole immediate purpose of continuing a violation of law." Id. at 501, 69