You may recall the ruling of April 27, where one of the points of the alleged breach of privilege was a letter from an ADM, and the Speaker ruled, “I have to see what use is made of the letter.” It's not enough to write a letter stating an opinion; it's question of taking that letter and using it to interfere with a witness. There was no evidence of that before the House, so the Speaker wasn't able to find a breach of privilege.
On June 15th, 2010. See this statement in context.