Edward Snowden’s disclosures and subsequent government declassifications have prompted a wave of proposals to retool the Foreign Intelligence Surveillance Act (“FISA”). Some of these proposed revisions are new; others merely reprise older ideas which were put forward earlier in Congress, as recently as 2012.

Rare bipartisan alliances have coalesced during the debate—ones that have more to do with attitudes towards government surveillance and which committees members lead than they do with party affiliation. On one side, you’ll find the leaders of the Senate Select Committee on Intelligence, Chairwoman Dianne Feinstein and Ranking Member Saxby Chambliss. On the other are the Chairman of the Senate Judiciary Committee, Patrick Leahy, and former House Judiciary Chairman James Sensenbrenner—along with Senators like Ron Wyden, Richard Blumenthal, Mark Udall, Al Franken, Rand Paul and Mike Lee and a motley crew of House members too.

Broadly speaking, the pending FISA reform bills address one or more of the following major issues: the substantive reach of surveillance activities under the statute; the procedures used in the two FISA-created courts; the processes by which the courts’ judges are selected; and the transparency and reporting requirements governing surveillance under the FISA. Thursday, the SSCI approved legislation supported by Senators Feinstein and Chambliss; just before that, Senator Leahy and Rep. Sensenbrenner put forward a competing proposal. What follows is an overview of these and other bids to rework FISA.

The Substantive Scope of FISA

The SSCI bill—what we’ll call “Feinstein-Chambliss“—would affirm the legality of controversial NSA surveillance programs, while codifying in statute restrictions on access to and use of information gleaned from such programs. The legislation also would tackle what its authors see as a worrisome, surveillance-stopping scenario (or “collection gap,” to borrow the intel jargon), in which a foreign target crosses into the United States, but the government has not yet obtained a warrant authorizing continued eavesdropping.

Regarding the latter, the SSCI-approved legislation would permit, in exigent circumstances, continued surveillance of a non-U.S. person who has entered the United States, for 72 hours following the government’s recognition that this person is likely within the United States. During the 72-hour interval, the government could request a court order under traditional FISA to conduct further surveillance; alternatively, and in an emergency, the Attorney General could unilaterally certify that continued surveillance is required. But absent such certification or a court order, the government would be obliged to destroy information obtained after the 72 hour period’s lapse. This would effectively close the gap the government currently believes exists, avoiding a situation in which needed surveillance is unilaterally suspended at the moment the subject crosses into U.S. territory (a potentially critical moment in an investigation) but is then renewed some time later after the government has persuaded a judge to permit surveillance to continue. The provision permits a shorter collection timeframe than do existing emergency authorization provisions in other parts of FISA.