What is a Level 3 sex offender in the US?

Level 3 sex offenders: Have a high risk of re-offending. Pose a high degree of danger to the public.

What did a Level 4 sex offender do?

LEVEL 4: Sexually Violent Predator refers to a person who has been adjudicated guilty of a sex offense or acquitted on the grounds of mental disease or defect of a sex offense that makes the person likely to engage in predatory sex offenses.

Do all 50 states have a sex offender registry?

Today all 50 states and the District of Columbia have them. Federal law now requires states to maintain sex offender registries and has limited state discretion regarding who must register, and for how long.