I think the FISA court was originally introduced because the State was abusing its power by illegally spying on citizens and the FISA court was meant to replace

I think the FISA court was originally introduced because the State was abusing its power by illegally spying on citizens and the FISA court was meant to replace this unregulated illegal spying with legal spying regulated by a court. I guess the better solution may have been to stop the spying all together but FISA court was probably an improvement on the existing practices.