Exactly, the NSA straight lied to congress about whether they were spying on Americans. If they’re willing and able to openly flout the entire legislative branch, I don’t see why they wouldn’t do the same to the judicial.
When a government agency like the NSA, CIA, or DOD has that much power, they become effectively sovereign. This is related to the idea of the deep state: While there is no secret conspiracy to control the government, the people who are ostensibly running it are not in fact in charge.
Therefore, it’s naive to look to the courts or congress or the president to solve these problems. We must look to each other, and work together to make mass-surveillance impossible.