Yesterday, the Second Circuit Court of Appeals, which oversees New York, Vermont, and Connecticut, determined that using an erection-measuring device as part of probation for one sex offender was an "extraordinarily invasive" and a violation of due process.

As part of his probation, convicted sex offender David McLaurin underwent "plethysmograph examinations," in which a device was "attached to the subject's penis" and "the subject is then required to view pornographic images or videos while the device monitors blood flow to the penis and measures the extent of any erection that the subject has."

In a similar case in 2001, the Ninth Circuit Court of Appeals explained that erection-measuring "has become routine in the treatment of sexual offenders." Plethysmography advocates, like the Council on Sex Offender Treatment in Texas, contend that although the procedure cannot be used to prove anything in court, it can help gauge a sex offender's likelihood of recidivism.

The Second Circuit Court of Appeals saw some problems with the claims of plethysmography's effectiveness. The judges wrote, "We find it odd that, to deter a person from committing sexual crimes, the Government would use a procedure designed to arouse and excite a person with depictions of sexual conduct closely related to the sexual crime of conviction."

The rights-violating and "unduly intrusive" examination stems not from the actual sexual crimes McLaurin committed. In fact, a previous court had determined him "unlikely to reoffend again." Rather, a bureaucratic slip-up led to him enduring plethysmography. McLaurin failed to fill out a form registering his address when he moved from Alabama to Vermont in 2011. Subsequently, he was sentenced to 15 months in prison and five years probation. His sentencing included the option, but did not require, that McLaurin could undergo plethysmogrophy.

The judges overseeing his appeal stated that they "fail to see any reasonable connection between this defendant, his conviction more than a decade ago, his failure to fill out paperwork, and the government-mandated measurement of his penis."