The overall conclusion is that Megan's law has had no demonstrated effect on sexual offenses in New Jersey, calling into question the justification for start-up and operational costs. Megan's Law has had no effect on time to first rearrest for known sex offenders and has not reduced sexual reoffending. Neither has it had an impact on the type of sexual reoffense or first-time sexual offense. The study also found that the law had not reduced the number of victims of sexual offenses. Sentences received prior to the implementation of Megan's Law were nearly twice as long as those received after the law's passage, but time served has been approximately the same before and after the law's enactment. Significantly fewer sexual offenders have been paroled after the implementation of Megan's Law, largely due to changes in sentencing. Start-up costs were $555,565, and current costs (2007) were approximately $3.9 million for the responding counties. The study involved three methodologies and samples. Phase one involved a 21-year trend study of sex offenses in each of New Jersey's counties and the State as a whole. This period covered 10 years prior to and 10 years after the law's implementation, as well as the year of implementation. Phase two obtained data on 550 sexual offenders released from 1990 to 2000, with attention to outcomes of interest. Phase three collected data on implementation and ongoing costs of administering the law. 7 tables, 8 figures, and 25 references