Lawyers Ted Olson and David Boies on Wednesday endorsed a bill that seeks to bar anti-LGBT discrimination in all areas of civil rights law.

The bill, titled the Equality Act of 2015, is expected to be unveiled during a press conference at noon on Thursday.

(Related: Democrats to introduce LGBT protections bill Thursday.)

In a joint statement, Olson and Boies, the legal team that successfully challenged California's ban on gay marriage, Proposition 8, said that the bill was needed to protect the livelihoods of “many of the same couples who fought so long and so hard to have their marriages recognized.”

“The introduction of the Equality Act marks a historic moment for our country,” Olson and Boies said. “The patchwork of protections in this country has provided a crazy quilt of laws, threatening the livelihood of many of the same couples who fought so long and so hard to have their marriages recognized. That’s why we support the idea of a comprehensive approach to non-discrimination protections that would embrace LGBT people as other groups who are protected by our civil rights laws. We urge Republicans and Democrats to once again come together to support this important legislation that provides the same protections to LGBT people as other Americans.”