A New Jersey Democrat known as one of the state’s most liberal legislators has abruptly resigned, just one week after child pornography was found on his legislative office computer.

Veteran state Assemblyman Neil Cohen sent the clerk of the Assembly a one-sentence letter this morning saying his resignation is effective immediately. Serving his 17th year in the New Jersey Assembly, Cohen was a deputy speaker who chaired two highly regarded committees and was a member of the legislature’s Joint Committee on Ethical Standards.

Last week two colleagues who share a legislative district office with Cohen reported him to state investigators after an aide discovered images of child pornography in his government computer. The fellow lawmakers, Senator Raymond Lesniak and Assemblyman Joseph—both Democrats from the same district—conducted an internal probe before reporting the disturbing facts to the attorney general’s office.

It turns out that several legislative staffers had seen inappropriate images on Cohen’s computer as well as printouts of nude young girls that originated from his electronic files. State police officials subsequently confiscated the computer and its files and Cohen, a divorce attorney, is reportedly in a psychiatric facility.

Ironically, Cohen sponsored a law to create a 24-hour hotline for members of the public to report computer crimes, including child pornography and he co-sponsored legislation to retroactively remove immunity from churches, schools and other charities that negligently hire employees who sexually abuse children.