Americans may find out in the next month just how many of them have been spied on through the intelligence community’s foreign digital surveillance programs, Reuters reported Friday afternoon, citing a letter to Director of National Intelligence James Clapper obtained by the newswire.

In the letter, 11 members of the House Judiciary Committee informed Clapper, who recently announced his resignation, that his staff and officials from the National Security Agency had described to the committee how the intelligence community would disclose the number of Americans whose electronic messages had been collected.

The disclosure is set to arrive just as Congress is likely to begin debating the merits of a provision of the 2008 Foreign Intelligence Surveillance Act known as Section 702, which expires at the end of 2017.

Section 702 allows the U.S. government to spy on anyone “reasonably believed” to be outside American borders, while prohibiting surveillance of people within the U.S. However, as the Washington Post found, the NSA’s searches are “designed to produce at least 51 percent confidence in a target’s ‘foreignness.’” This allows the intelligence community to “incidentally” collect information passed between Americans and foreigners, and that trove of information could be quite large, according to a report by the Brennan Center.

Critics pointing to Section 702’s loopholes have called it a “backdoor” method of mass surveillance of American citizens.

As the letter showed, the number of Americans included in that data collection could soon be declassified, something Congress has long pushed for, but that Clapper has long resisted. As NPR reported in April, the intelligence chief has said that “any methodology we come up with will not be completely satisfactory to all parties,” and that if such an estimate were feasible, “we would’ve done it a long time ago.”

The revelation of the number of Americans affected, as the Judiciary Committee members noted in the note recently obtained by Reuters, could decide Section 702’s fate.

“The timely production of this information is incredibly important to informed debate on Section 702 in the next Congress,” the letter said, according to Reuters. The Committee added that, without the figure, “even those of us inclined to support reauthorization would have reason for concern.”