Always fascinating to see Congress expressing shock that the legal and national security systems it created are operating as Congress required them to.
For example, FISA doesn't require (or even really contemplate) hearings before a court grants a wiretap application. If lawmakers are shocked by that, as some profess to be, they could of course change the law.
To date, some lawmakers have professed to be shocked by many common features of federal aw enforcement: Ex parte warrant applications, the FBI using dodgy informants, early-morning searches, using informants, etc. But the shock has been confined to a single investigation.
A test of whether they're as scandalized as they claim will be whether they're willing to change the rules for *other* people, too.
There's a not-small constituency that's been pretty vocal about reigning in the federal government's law enforcement powers, and no shortage of examples of their being used in a heavy-handed way. But so far, Congress hasn't been particularly interested.
Also worth thinking about what might have happened if the FISC had held a hearing before granting a Title I surveillance order against Carter Page. What would that have looked like?
Page obviously wouldn't have been invited. The judge could have asked DOJ questions. But FISC judges have a different process for doing that, which it uses more often. FISC rules require DOJ to submit proposed applications; judges then can express concerns without a hearing.
Could the judge have demanded additional evidence? Maybe. But the statute is pretty clear that the determination of whether the application supplies probable cause is to be made "on the basis of the facts submitted by the applicant." 50 U.S.C. § 1805(a)(2).
Perhaps the judge could have decided this is an unusual circumstance and he'd hold the government to a higher standard? The statute doesn't really give a judge that discretion. 50 U.S.C. § 1805(a) sets a probable cause standard; if that's met, the judge "shall" issue the order.
Perhaps the judge could have added some additional minimization procedures, or restricted the scope of the search. But FISC judges can (and apparently do) do that without holding hearings, and that part of the order is still sealed, so we have no idea whether it happened.
And this ->
Also, finally, you might have heard the contention that it was new or unprecedented for the gov't to carry out secret searches related to a presidential campaign. In truth, it wasn't even the first time that had happened in the 2016 campaign. 
The FBI's requests for search warrants related to Clinton's emails generally were approved the same day by a federal magistrate judge, which is also how things usually work.
