To answer that question, personally I don't think it's relevant. I am sure that groups that have received the court challenges program funding in the past may have been candidates for different parties in the past. I do believe, to answer your question, that Mr. Carpay was a Reform Party candidate at some point.
Evidence of meeting #58 for Official Languages in the 39th Parliament, 1st session. (The original version is on Parliament’s site, as are the minutes.) The winning word was rights.
A recording is available from Parliament.