SAN FRANCISCO (CBS SF) – San Francisco right hander Matt Cain has become the latest celebrity to be photographed as part of the NoH8 campaign for gay, lesbian, bisexual and transgender rights.

The campaign was established in response to California’s 2008 passing of Proposition 8, which amended the state constitution to ban same-sex marriage. According to founders Adam Bouska and Jeff Parshley, the photographic protest, which is known for depicting celebrities and ordinary people with a piece of duct tape over their mouths, symbolizes voices being silenced by Prop. 8.

Cain, the longest tenured Giant, was featured by the campaign Thursday as the photo of the day. The Alabama native is identified by the NoH8 as an “LGBT Ally.” He was one of several Giants to appear in a video for the It Gets Better Campaign. The Giants were the first professional team to join the anti-harassment campaign.

The 27-year-old signed a five-year contract extension in the offseason. On June 13th, he pitched the 22nd perfect game in Major League history and first in franchise history.

(Copyright 2012 by CBS San Francisco. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)