DENVER (AP) -- Colorado lawmakers will begin an ethics investigation against a Republican lawmaker whose traffic stop has rocked the stability of the House GOP.

A committee of lawmakers is meeting for the first time Monday to discuss the case of Collbran Rep. Laura Bradford. Denver police say officers suspected she was driving drunk late on Jan. 25 but that they couldn't detain her because of a constitutional provision that protects lawmakers during session. Police have apologized for mischaracterizing the traffic stop and alleging she used her position to avoid arrest.

The episode has created a rift for Republicans. Bradford has threatened to leave her party, jeopardizing the GOP's one-vote advantage in the House.

Bradford could still face a charge for having a gun in her car while allegedly intoxicated.

(COPYRIGHT 2011 BY THE ASSOCIATED PRESS. ALL RIGHTS RESERVED.)