After voting down reform three reform amendments on Thursday, the Senate continued debate on the spy bill on Friday morning. Sen. Ron Wyden (D-Ore.) offered an amendment meant to force the National Security Agency and the Central Intelligence Agency to reveal how frequently they have collected Americans’ communications as part of their efforts to amass intelligence on foreign targets. Even an estimate would suffice, Wyden has argued — but the spy agencies have rebuffed his efforts to get a general number, claiming it is not possible.

“This is the last oportunity for the next five years for the Congress to exercise a modest measure of real oversight over this intelligence surveillance law,” said Wyden, referring to the 2017 expiration date in the new law. “It is not real oversight when the United States Congress cannot get a yes or no answer to the question of whether an estimate currently exists as to whether law abiding Americans have had their phone calls and emails swept up under the FISA law.”

Wyden and other civil liberties advocates are worried that the spy agencies might be able to use intelligence gathering capabilities ostensibly targeted at foreigners — a legal practice under the law — to search their databases for Americans’ emails and phone calls without a warrant.

The FISA Amendments Act was first approved during former President George W. Bush’s time in office, though its passage has been relatively uncontroversial in comparison to the initial vote in 2008. It is worth noting that then-candidate Barack Obama vowed to block such programs, while on the campaign trail in 2008, before switching to a push for simply increasing oversight/accountability of such programs.