This blew my mind.

If members of Congress had been arrested would we even know?

Parliamentary immunity

United States

Main article: Speech or Debate Clause

Mason's Manual notes, "The courts, by a series of decisions, have explained away almost every essential feature of the privilege from arrest as it once existed…A member of the legislature has no right to physically resist an officer attempting to make an arrest to the extent of assaulting such officer."[20]

Members of the United States Congress enjoy a similar parliamentary privilege as members of the British Parliament; that is, they cannot be prosecuted for anything they say on the floor of the House or Senate. They also enjoy the right to be present in Congress: that is, they may be in prison or jail the rest of the time, but they have the right to attend Congressional sessions, speak on the floor, vote, etc. These rights are specified in the Constitution and have been fairly uncontroversial in U.S. history. Courts have consistently interpreted them very narrowly.

Several state constitutions provided equivalent protections for members of state legislatures.

https://en.wikipedia.org/wiki/Parliamentary_immunity#United_States