U.S. Rep Chip Roy, a vocal critic of Ken Paxton and a firebrand within the GOP, is running to take over for Paxton as Texas ...

Texas, is running to become the Lone Star state's next top prosecutor, announcing a campaign for Texas' attorney general on Thursday.

The policy chair of the House Freedom Caucus, Roy has made a name for himself as an outspoken member who isn’t afraid to take unpopular positions if he believes it violates his principles.

It will be the first test of whether Roy’s at times frosty relationship with President Trump — and his turn against Paxton — can withstand scrutiny in a statewide primary.