The Adam Walsh Child Protection and Safety Act became law in 2007. This law implements new uniform requirements for sex offender registration across the states. Highlights of the law are a new national sex offender registry, standardized registration requirements for the states, and new and enhanced criminal offenses related to sex offenders. Since its enactment, the Adam Walsh Act (AWA) has come under intense grassroots scrutiny for its far-reaching scope and breadth. Even before any state adopted AWA, several sex offenders were prosecuted under its regulations. This has resulted in one life sentence for failure to register, due to the offender being homeless and unable to register a physical address. 
In the United States, all 50 states have passed laws requiring sex offenders, (especially child sex offenders), to register with police. They report where they live when they leave prison or are convicted of a crime.
In 2006, California voters passed Proposition 83, which will enforce "lifetime monitoring of convicted sexual predators and the creation of predator free zones. This proposition was challenged the next day in federal court on grounds relating to ex post facto. The U.S. District Court for the Central District of California, Sacramento, found that Proposition 83 did not apply retroactively.
Patty Wetterling, the mother of Jacob Wetterling and a major proponent of the Jacob Wetterling Act has openly criticized the evolution of sex offender registration and management laws in the United States since the Jacob Wetterling Act was passed.
Canada's National Sex Offender Registry (NSOR) came into force on December 15, 2004, with the passing of the Sex Offender Information Registration Act (SOIRA) Since then, any offender who is convicted of a designated sexual offence may be ordered, at the time of sentencing or as soon as possible thereafter, by the court to register with the registration site that serves the area of their main residence. A person so ordered must register within 15 days, or if they are incarcerated for their crime, within 15 days from their release date. The information that is collected from the offender is confidential, and is not available to the public.
The main purpose of Canada's NSOR is to assist a police officer who is investigating a crime of a sexual nature. NSOR analysts can provide the most current information available about a suspect who is already a registered sex offender, or can search the NSOR database for possible suspects in sexual offence cases where the offender is unknown.
The NSOR database also contains details concerning many sex offenders who were convicted and sentenced prior to December 15, 2004, referred to as "retrospective" offenders, the criteria being that they must have still been serving an active portion of their sentence on the date that the SOIRAct came into force (eg. still incarcerated, on probation, or on parole). These retrospective offenders were tracked down by various law enforcement authorities, and were served with a Notice that they were required to register for the NSOR after a one-year grace period. The last day of that grace period was December 15, 2005.
Anyone required to register with Canada's National Sex Offender Registry is required to comply with the following obligations:
1) to register with their registration site once a year. (The registration site is usually the police agency that serves the area where the offender's main residence is located, although this description varies somewhat by province or territory);
2) to advise their registration site, within 15 days, of any change of name;
3) to advise their registration site, within 15 days, of any change of address;
4) to advise their registration site, within 15 days, of any absence from their main address that will be for at least 15 consecutive days. They must advise of their date of departure, their actual or estimated date of return, and of the address(es) where they will be while absent. In addition, the offender is required to advise the registration site, within 15 days of their return to their residence, of their actual date of return.
An Order or Notice requires an offender to comply with the SOIRAct for a term of either 10 years, 20 years, or Life. The term is determined by the maximum possible penalty the offender could have received for the offence for which he/she was sentenced. Also, if the offender has a previous conviction for any sexual offence (it does not have to be the same sexual offence for which they're now being sentenced), or if they're already under a previously-issued Order or Notice, the minimum term that will apply, is Life.
See Violent and Sex Offender Register
Teenagers have been forced to register after being convicted of having consensual sex with other teens in a Jersey City ordinance. In some states, adults who have been convicted of having consensual sex, (especially, nonmarital sex) are also required to regisiter as sex offenders as well. 
In California, some types of drug offenders must comply with registration closely resembling that of sex offenders, although drug offender registration is not life-long. Examples of drug convictions requiring registration are heroin possession and marijuana sales to minors on school grounds. This type of registration expires five years after the felon completes his or her probation or parole period, if that person has remained arrest-free.
In New York and various other states, crimes that society does not necessarily view as sexual in nature are also considered to be registerable sex offenses, such as kidnapping, unlawful surveillance, "sexual misconduct" (such as mooning or streaking), unlawful imprisonment, and in some cases "sexually motivated offenses" (such as assault, burglary, etc.) that are not categorized as sexual offenses unless the court determines that the offense was committed pursuant to the offender's own sexual gratification.
Sex offenders who have completed probation or parole may also be subject to restrictions above and beyond those of most felons. In some jurisdictions they cannot live within a certain distance of places children or families gather. Such places are usually schools, churches, and parks. It could also include public venues (stadiums), apartments, malls, stores, shopping centers, and certain neighboorhoods.
In most places sex offenders are subjected to an exit ban, meaning that they can't travel or leave a certain place at a certain time; most often the offender cannot leave his hometown without permission from a probation officer. They may also be subjected to the TSA's No fly list. The exact provisions vary with each locality.
Some states have Civil Commitment laws, which allow very-high-risk sex offenders to be returned to prison or forced to live under very heavy supervision after the end of their normal sentences. See also: Child Sex Offender penalties.
Dr. Henry Rogan of the University of Santa Barbara has this to say about convicted sex offenders: "[The ‘predator-free’ zone] doesn’t solve anything." He remarked in a recent interview, “It’s just punishment. Sex offenders don’t pick up people they don’t know -— that’s what kidnappers are for.”
Sex offender registries are designed to protect and alert the public about the dangers of sex offenders; however, in at least two instances, convicted sex offenders were murdered after their information was made available over the internet.
Accordingly, in order to enforce the sex offender registration law, all potential registrants would have to have hearings to determine their individual "dangerousness." Thus, because of the expense involved in doing so, although Hawaii's sex offender registration law remained in the statute books, it was rendered unenforceable, and the online registry was removed.
On May 9, 2005, however, two years after the Supreme Court of the United States's decision that sex offender registration did not violate Due Process, the Hawaii Sex Offender website was put back on-line. Hearings are no longer required to determine whether an offender's registration information may be placed online. This has not been challenged again under the Constitution of Hawaii.
In Doe v. Phillips, 194 S.W.3d 837 (Mo. banc 2006), the Supreme Court of Missouri in Jefferson City held that it violated the Constitution of Missouri's unique bar on retrospective laws to apply Missouri's sex offender registry to anyone who had been convicted or pleaded guilty to a registrable offense before the sex offender registration law was passed in 1995. The Court ruled that any potential registrant who pleaded guilty or was convicted before January 1, 1995, did not have to register, and remanded the case for further consideration in light of that holding. On remand, the Circuit Court of Jackson County, Missouri entered an injunction ordering that the applicable individuals be removed from the published sex offender list. The Missouri State Highway Patrol appealed that order to the Missouri Court of Appeals in Kansas City, which affirmed the injunction on April 1, 2008. The Highway Patrol indicated that it may attempt to appeal to the Supreme Court of Missouri.
The 2006 Doe ruling prompted a flurry of similar lawsuits throughout Missouri. In July of 2007, in Doe v. Blunt, 225 S.W.3d 421 (Mo. banc 2007), the Supreme Court of Missouri held that the 2006 ruling applied to potential registrants whose offenses did not become registrable (via amendment into the Sex Offender Registration Act) until after they pleaded guilty or were convicted, and thus could not be required to register. On February 19, 2008, the Supreme Court of Missouri held that the Missouri Constitution's bar on retrospective laws also prohibited enforcement of a requirement that a registered sex offender move from his home located within 1000 feet of a school when he lived in that home prior to the enactment of the law requiring that he move.
In response to these rulings, in 2007, several State Senators in the Missouri General Assembly proposed an amendment to the Missouri Constitution which would exempt sex offender registration laws from the state constitution's unique prohibition on retrospective civil laws. The proposed amendment passed the Missouri State Senate unanimously, but was not passed by the House of Representatives before the end of the 2007 legislative session. If the House of Representatives had passed the measure, it would have had to be approved by voters in the 2008 general election in order to be ratified. Because the House did not pass it in time, however, the end of the legislative session terminated consideration of the proposed constitutional amendment. The same constitutional amendment was proposed in and passed by the Missouri Senate again in 2008, but also was not passed by the House of Representatives by the end of the 2008 legislative session.
As a result, the decisions of the Supreme Court of Missouri and the Missouri Court of Appeals prohibiting the retrospective application of sex offender laws remain intact.