This makes the FISA process unique because it involves all three branches of government. For example, Congress has created its own rules to oversee electronic surveillance and judges approve or deny the requests for warrants. These are in addition to the internal oversight tools that the executive branch has. The checks and balances for FISA are quite robust compared to the ones that exist for other presidential national security powers like the authority to approve drone strikes.

I know firsthand that it’s difficult to get a FISA warrant. From 2002 to 2005, when I was an F.B.I. agent conducting counterintelligence investigations in New York, my FISA applications went through many layers of approval and required very strong evidence. It was clear to me that the process was set up to protect against abuses of power.

This process has been in place for 40 years and the Republican Party has never meaningfully objected to it — until now. It’s important to realize that it’s not the FISA system itself that Republicans believe is the problem, but the people involved. That’s a complaint they share with progressives.

In criticizing the FISA process, the left has not focused so much on fixing procedural loopholes that officials in the executive branch might exploit to maximize their legal authority. Progressives are not asking courts to raise the probable cause standard, or petitioning Congress to add more reporting requirements for the F.B.I. Instead, progressives complain that law enforcement officials, along with judges, will always act in bad faith and try to circumvent the law altogether — and that’s why the FISA process can’t be trusted.

The most popular example of this critique, particularly since the Sept. 11 attacks, centers on the number of FISA applications the court turns down, which is almost zero. In other words, if an F.B.I. agent submits a petition to the FISA court, it is extremely likely to be approved. Based on this, privacy advocates conclude that the court is effectively a rubber stamp, allowing the F.B.I. to get away with applications for surveillance that have no real legal basis.