“I have tried to live a life of principles,” Judge Carlos Key says in the opening of his new ad.

The Bexar, Texas County Criminal Court #11 jurist goes on to explain how intolerance in the Republican Party both on the local and national levels has convinced him to leave the GOP he once called home, and run for re-election as a Democrat:

I can no longer be a member of the Republican Party.

For too long, the Republican Party has been at war with itself. Rational Republican beliefs have given way to ideological character assassinations. Pragmatism and principal have been overtaken by pettiness and bigotry. Make no mistake: I have not left the Republican Party. It left me.

I cannot tolerate a political party that demeans Texans based on their sexual orientation, the color of their skin or their economic status.

I will not be a member of a Party in which hate speech elevates candidates for higher office rather than disqualifying them. I cannot place my name on the ballot for a political party that is proud to destroy the lives of hundreds of thousands of federal workers over the vain attempt to repeal a law that would provide health care to millions of people throughout our country.

Key is clearly referencing the government shutdown led by the refusal of Senator Ted Cruz (R-TX) and the House Republican “Suicide Caucus” to fund the Affordable Care Act, which has sunk the party new lows in several polls.

He’s also alluding to recent comments by Republican City Councilwoman Elisa Chan that were secretly recorded during a meeting about San Antonio’s non-discrimination policies:

You know, to be quite honest, I know this is not politically correct. I never bought in that you are born, that you are born gay. I can’t imagine it.

I don’t think homosexual people should do adoption. … You’re going to confuse those kids. They should be banned.

If you wanted to choose that lifestyle, we don’t want to discriminate you, but you shouldn’t affect the young people. How terrible. … They’re going to be confused. You see two men go into a bedroom. You see two women kissing. Is that not confusing? It’s confusing.

So disgusting.

“My principles have led me to the Democratic Party,” Key said, before giving out his Twitter handle and website address. “I can only hope more people of principle will follow me.”

Key spoke with MSNBC’s Thomas Roberts on Tuesday about his decision to leave the GOP:

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