That's not really a problem when intelligence services can just "remind" any would-be annoying congress person that they have endless amounts of data showing exactly what they and their family members have been doing and could plant whatever they want into the data they already have.
One of the things that finally convinced Snowden to give up everything he had in order to tell the American people that the NSA was violating their constitutional rights was when he watched NSA director James Clapper outright lie right to the faces of congress. After the truth came to light, do you think Mr. Clapper faced any meaningful consequences for that? Nope. Can you guess why not?
Intelligence services are too powerful to be held accountable by anyone. They'll do whatever they want.