Question: can the speaker of the house block a bill

Answer: Yes, The Hastert Rule, also known as the ``majority of the majority'' rule, is an informal governing principle used in the United States by Republican Speakers of the House of Representatives since the mid-1990s to maintain their speakerships and limit the power of the minority party to bring bills up for a vote on the floor of the House. Under the doctrine, the Speaker will not allow a floor vote on a bill unless a majority of the majority party supports the bill.