Stephen Collins -- Resigns From Screen Actors Guild Board

Stephen Collins has resigned his position on the National Board of the Screen Actors Guild ... following our story that Collins confessed to child molestation and/or exposing himself to 3 young girls.

A rep for SAG/AFTRA tells TMZ ... Collins resigned today, prior to his 3-year term coming to an end.

Collins was also fired from "Ted 2" Tuesday morning, in addition to being wiped from the website of the Committee For Stress-Free Schools -- where he had been a Co-Director -- which is part of the David Lynch Foundation.

The NYPD has an active investigation into the allegations.