The last 10 years have seen an increased use of British civil law to contain and incapacitate sex offenders. This has occurred in tandem with changes in criminal law that have increased sentence length and extended supervision periods. This paper uses the sex offender "register" as a case study of a civil measure that has evolved under the influence of popular opinion reflected in the media rather than with reference to substantive evaluations and research. The sex offender register, which was begun in 1997 as a civil measure, requires that anyone convicted of a designated sex offense notify the police every time they change their name or address over a specified period of time. More stringent modifications of registration provisions have occurred in response to repeat sex offenses against children; for example, the penalty for failure to comply with registration requirements has evolved from an initial maximum of 6 months imprisonment to a possible 5 years. Although access to sex offender information in the register has not yet been open to the public, there has been public pressure to do so. The increasingly restrictive measures for sex offenders who live in communities after serving prison time have not been scientifically tested to determine their effectiveness in preventing recidivism. In addition, they have become a form of social control that is unconstrained by concepts of due process or proportionality in the face of ever more severe consequences for violations. 27 references