Carr v. United States


May SORNA apply to a sex offender whose conviction and interstate travel both predated SORNA’s enactment?

Oral argument: 
February 24, 2010


The Sex Offender Registration and Notification Act (“SORNA”) requires convicted sex offenders to register in any jurisdiction in which the offender resides and imposes criminal penalties on any sex offenders who travel in interstate commerce and knowingly fail to register. Before SORNA was enacted, Thomas Carr, a convicted sex offender, moved to Indiana but failed to register. A federal grand jury indicted Carr for his failure to register under SORNA. Carr appealed to the U.S. Circuit Court of Appeals for the Seventh Circuit, arguing that applying SORNA violated the ex post facto clause as his conviction and travel predated SORNA. The Seventh Circuit held that SORNA did not violate the ex post fact clause because the failure to register occurred after SORNA was enacted. The Supreme Court’s decision will settle a circuit split over whether SORNA can punish sex offenders who traveled in interstate commerce before its enactment.

Questions as Framed for the Court by the Parties 

The President signed the Sex Offender Registration and Notification Act (“SORNA”) into law on July 27, 2006. Pub. L. 109-248 §§101-55, 120 Stat. 587. SORNA requires persons who are convicted of certain offenses to register with state and federal databases. See 42 U.S.C. § 16913(a). The law imposes criminal penalties of up to ten years of imprisonment on anyone who “is required to register * * * travels in interstate or foreign commerce * * * and knowingly fails to register or update a registration.” 18 U.S.C. § 2250(a). On February 28, 2007, the Attorney General retroactively applied SORNA’s registration requirements to persons who were convicted before July 27, 2006. 72 Fed. Reg. 8896, codified at 28 C.F.R. § 72.3. The two questions presented are:

1. Whether a person may be criminally prosecuted under § 2250(a) for failure to register when the defendant’s underlying offense and travel in interstate commerce both predated SORNA’s enactment.

2. Whether the Ex Post Facto Clause precludes prosecution under § 2250(a) of a person whose underlying offense and travel in interstate commerce both predated SORNA’s enactment.


Article I, Sections 9 and 10 of the Constitution prohibit the passage of ex post facto laws. Ex post facto laws retroactively criminalize conduct that was legal at the time it was committed; ex post facto laws would allow for increased punishment after the fact, as well as an inability to avoid prosecution by altering one's conduct. 

The federal government and every state have passed registration laws for sex offenders.  In 2006, Congress supplemented what were seen as deficiencies in state registration laws by passing the Sexual Offender Registration and Notification Act (“SORNA”).  SORNA requires sex offenders to register in all jurisdictions in which the offender resides, works, or is a student.  Moreover, SORNA imposes criminal penalties on any convicted sex offender who travels in interstate commerce who knowingly fails to register as a sex offender, unless he or she can prove that “uncontrollable circumstances” prevented registration.  Congress also gave the Attorney General authority to decide whether to apply SORNA to sex offenders convicted before SORNA’s enactment.  On February 28, 2007, the Attorney General issued a regulation expanding SORNA’s applicability to cover pre-SORNA sex offenders.  This made SORNA applicable to the Petitioner, Thomas Carr. 

In 2003, before the enactment of SORNA, Thomas Carr pled guilty to a charge of first-degree sexual abuse in Alabama state court and received a fifteen-year sentence.  Carr was released from prison in July of 2004 and registered with Alabama in compliance with then-existing registration requirements.  Sometime later, Carr moved from Alabama to Indiana. 

On July 9, 2007, approximately five months after the Attorney General declared SORNA applicable to existing sex offenders, police arrested Carr on unrelated grounds.  A federal grand jury indicted Carr under SORNA.  Carr plead guilty on the condition he would be allowed to appeal.  Carr appealed to the U.S. Circuit Court of Appeals for the Seventh Circuit

The Seventh Circuit consolidated Carr’s appeal with that of a similarly situated defendant, Marcus Dixon.  Both Carr and Dixon argued that their convictions and their interstate travel pre-dated SORNA and thus, that their convictions violated the ex post facto clause.  The Court held that SORNA did not violate the ex-post facto clause, because the failure to register occurred after SORNA’s enactment.  The Court overturned Dixon’s conviction on the ground that he was not given a reasonable time to comply with SORNA’s requirement The Seventh Circuit affirmed Carr’s conviction, however, on the ground that five months was a more than reasonable time in which to comply with SORNA’s requirements after the Attorney General’s Regulation made SORNA applicable to him. Carr appealed his conviction to the Supreme Court

The U.S. Supreme Court granted certiorari to determine whether convicting Carr under SORNA violates the ex post facto clause given that his sex offender conviction and travel predated SORNA.


This case turns on whether or not the Sex Offender Registration and Notification Act (“SORNA”) may apply to sex offenders who traveled interstate before SORNA’s enactment.

I. Interpreting the Statute

A. The Rules of Statutory Interpretation

Petitioner Thomas Carr argues that statutory interpretation of SORNA requires that travel only include travel that occurred post-SORNA.  First, the rule of lenity dictates that courts will resolve any ambiguities in a statute to favor criminal defendants where a harsher interpretation cannot be clearly supported as correct.  Carr also points out that the principle of the presumption against retroactivity applies.  Accordingly, courts will avoid interpreting any statute to apply retroactively unless the statutory language clearly authorizes it.  Carr maintains that the Seventh Circuit incorrectly stated that the presumption against retroactivity only exists through the ex post facto clause of the Constitution.  Carr cites the Supreme Court’s holding that the presumption applies independent of the Constitution. 

Respondent United States insists that neither the rule of lenity nor the presumption against retroactivity apply in this case.  The United States points out that the rule of lenity only applies in cases where there is a “grievous ambiguity” in the statute’s meaning even after looking at the statute’s context and structure, which is not the case here.  Furthermore, the United States emphasizes that the rule of lenity is usually only used in cases where the underlying conduct is otherwise seen to be innocent.  In this case, Carr’s failure to register is a clearly wrongful act, regardless of when the travel took place.  The United States also maintains that, in the context of statutory interpretation, the presumption against retroactivity is no broader than the ex post facto clause.  In particular, the United States notes that the Supreme Court previously held that a statute does not automatically become retroactive because it is applied in a case where the conduct in question pre-dated the law’s enactment. 

B. Textual Interpretation

Carr argues that the word “travels,” as used in SORNA, must be interpreted in the present tense and thus cannot be made applicable to travel that had already occurred.  The Supreme Court has repeatedly held that present-tense verbs used in statutes cannot be made to apply to past acts, as according to common English usage.  Furthermore, Carr argues that the Dictionary Act, in which Congress specifically provided that words used in the present tense would include the future and the present, excludes by implication, past acts or events.  Carr maintains that the context of SORNA’s text as a whole implies that the word “travels” was meant to refer only to present and future acts, especially considering that Congress purposely delegated authority to the Attorney General to specify the retroactive effect of SORNA’s civil registration requirement but not the others.  Carr also points out that interpreting SORNA to include pre-SORNA interstate travel can lead to an absurd result because there are otherwise no limitations placed as to when that travel took place, so it could conceivably refer to interstate travel made at any time in a defendant’s life. 

In contrast, the United States argues that when interpreting the present-tense verbs used in SORNA in light of their context, the interstate travel cannot apply only to travel occurring after the enactment. The United States maintains that the only sequence required by SORNA is that of a conviction giving rise to a registration requirement, subsequent interstate travel, and a failure to register.  Beyond this sequence, the United States insists that the travel can occur before or after the enactment of SORNA.  The United States counters Carr’s reference to the Dictionary Act, by pointing out that the Dictionary Act’s clarification of the meaning of the present tense expressly provides for exceptions when the context calls for it. 

C. The Statute’s Purpose

Carr maintains that interpreting SORNA’s travel element to apply only to post-SORNA interstate travel is fully consistent with Congress’s purpose in enacting the statute.  Carr emphasizes that Congress intended for SORNA to correct the problem of loopholes in the earlier sex offender registration statutes by imposing uniform standards for the registration programs in the different jurisdictions.  Carr argues that making SORNA applicable to pre-enactment travel would have no effect on SORNA’s implementation, because unregistered sex offenders who have traveled in interstate commerce are no different from unregistered sex offenders who have not because both would still be subject to the state registration laws. 

However, the United States insists that including pre-enactment travel would further SORNA’s purpose.  The United States emphasizes the fact that Congress expressly mentioned interstate travel as being the primary way in which sex offenders avoided the state registration requirements. The United States affirms that the best way to register unregistered sex offenders would be by making SORNA immediately applicable, instead of waiting for them to cross state lines and fail to register again.  Furthermore, by enacting SORNA in the first place, Congress clearly demonstrated that it did not believe state enforcement of registration requirements was adequate to enforce SORNA. 

II. The Ex Post Facto Clause

Carr argues that interpreting SORNA to cover pre-enactment travel could violate the ex post facto clause in several ways.  First, if SORNA requires nothing more than registration under the pre-existing registration laws, then applying SORNA retroactively increases the punishment for the already-existing crime of not registering under the applicable state registration law.  The Supreme Court has already held that a law which applies to events that happened before its enactment and disadvantages the offender affected by it, violates the ex post facto clause.  Alternatively, if SORNA actually requires a different duty than the one required by the pre-existing registration laws, then applying SORNA to pre-enactment travel would violate the ex post facto clause by not giving Carr or anyone in a similar situation an opportunity to avoid liability for the new felony created by SORNA.   Carr emphasizes that the Supreme Court has previously held that any statute that denies an affected person the chance to avoid liability by altering his conduct violates the ex post facto clause and the Due Process clause.  Carr specifically points out that the Attorney General’s retroactivity regulation when combined with the statutory text would give him no opportunity to register, making him immediately guilty in a clear violation of the ex post facto clause.  Carr notes that the Seventh Circuit’s reading into SORNA a reasonable time period in which to register was entirely a judicial invention and invalid.  Carr stipulates that the only way to avoid an unconstitutional result is to interpret SORNA to apply only to post-enactment interstate travel. 

However, the United States maintains that the ex post facto clause is not violated, because the conduct that is criminalized is the knowing failure to register, and that could only have happened after SORNA was enacted.  The ex post facto clause applies only where the criminalized conduct was completed before the law’s enactment but not where, as in this instance, only some part of the conduct occurred before the law’s enactment.  The conduct that is punished is not simply the same as failing to register under the pre-existing statutes but, as SORNA expressly provides, failing to register or update a registration “as required by SORNA.”  The United States also emphasizes that Carr was not made immediately guilty upon the Attorney General’s retroactivity regulation, but was only found to have violated SORNA some months after the regulation was passed.  In particular, the United States notes that the Seventh Circuit found Carr to be guilty of violating SORNA only because he had not complied with its requirements after a “reasonable time” had passed. 


The principle that people should not be punished retroactively for past acts that they can no longer change is the basis for the prohibition against ex post facto laws.  This case presents the Supreme Court with the opportunity to settle a circuit split over the question of whether the Sex Offender Registration and Notification Act (“SORNA”) applies to convicted sex offenders who traveled in interstate commerce before the Act was passed. 

Petitioner, Thomas Carr, contends that allowing SORNA to capture conduct occurring before its enactment is a clear violation of the ex post facto clause. Both the National Association of Criminal Defense Lawyers (“NACDL”) and a group of law professors are concerned with the implications of setting a precedent permitting such a statute to pass constitutional muster.  The NACDL expresses concern that Carr’s punishment under SORNA is considerably higher than he would have been subjected to pre-SORNA, thereby conflicting with the Founders’ view that retroactive laws violated the fundamental principle of the social compact.  Law professors, as amicus curiae, point out that the ex post facto clause was meant to affirm the belief that laws should not unfairly punish unpopular groups that would otherwise be targeted by the legislature.  They argue that Carr’s retroactive conviction under SORNA is an example of public disapproval of a group leading to lawmakers imposing retroactive punishments on a maligned group. 

In contrast, the States of Kansas, Alabama, et al. (“States”) as amici curiae argue that the Court has previously held that sex offender registration laws do not violate the ex post facto clause because they are civil and regulatory statutes, and not punitive.  The States are concerned that finding a regulatory statute to violate the ex post facto clause would jeopardize a slew of other civil regulations, including attorney licensing or licensing for liquor sales and distribution.  The States argue that the legislature needs to be able to modify or amend such regulatory statutes often in order to better serve state goals. 

Carr asserts that making SORNA only applicable to post-enactment interstate travel would support SORNA’s main purpose of providing unity to the disparate rules governing sex offender registration among the various States.  The NACDL further argues that including only post-enactment travel into SORNA also serves Congress’ other purpose in enacting SORNA to reduce recidivism among sex offenders.  The NACDL emphasizes that registration programs such as that in SORNA have very limited effects in combating recidivism and indeed may even increase the risk of recidivism in sex offenders. The NACDL also asserts that interpreting SORNA broadly enough to include pre-enactment travel would hinder law enforcement officials in focusing on the sex offenders most likely to re-offend and thus hinder them in protecting the public. 

The United States insists that Congress’ main purpose was to solve the problem of sex offenders who go unregistered after traveling across state lines.  The United States argues that in enacting SORNA, Congress made a judgment that unregistered sex offenders constitute a threat to public safety and should be made to register. The States agree and further note that the Court has already held that such regulatory measures for sex offenders may properly impose further obligations on the offenders for the purpose of protecting the public from their danger. 


This case turns on whether Sex Offender Registration and Notification Act (“SORNA”) may be applied to sex offenders who traveled interstate prior to SORNA’s enactment. Thomas Carr argues that statutory interpretation and the  ex post  facto clause prohibit application where conviction and travel occurred pre-SORNA. The United States maintains that SORNA may apply to Carr as the failure to register occurred after SORNA’s enactment. The case is likely to affect the federal requirements for sex offender registration as well as clarify what constitutes an  ex post  facto law. It may also have an effect on state ability to enact certain regulatory laws.

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Additional Resources 

· Office of Sex Offender Sentencing, Monitoring, Apprehending, Registering, and Trafficking, U.S. Department of Justice

· Michael M. O’Hear, Seventh Circuit Week in Review: Limiting the Reach of the Adam Walsh Act (a Little), Marquette University Law School Faculty Blog, Dec. 28, 2008

· Sex Crimes: 7th Circuit Rules on SORNA Constitutionality (Jan. 5, 2009)