Sen. Josh Hawley (R-MO) is spearheading a contentious effort by some GOP lawmakers to scale back an investigation into the Department of Homeland Security Inspector General’s Office, according to The Washington Post. Inspector General Joseph Cuffari, a Trump appointee, has been probing the issue of the missing text messages from around the Jan. 6 insurrection for 15 months, but has refused to release some documents and tried to block some interviews. That has sparked a probe by a panel of federal watchdogs into various allegations of misconduct raised by whistleblowers and others, according to the Post. Adding to the concern, an April 1 memo written by employees in the IG’s office surfaced Thursday, revealing staff concerns that the Secret Service was flat-out refusing to comply with the probe. The Guardian reported that memo was passed on to Cuffari’s chief of staff so it could be included in Cuffari’s annual report to Congress—but it simply disappeared. The Post reports that the federal watchdog panel’s investigation of Cuffari’s office has turned into a “war of attrition” with some Republican lawmakers, led by Hawley, demanding investigators go easier on Cuffari’s office.

Editor’s note: Sen. Hawley’s actions relate to a probe that does not involve missing Jan. 6 text messages. This article has been updated to reflect an update made to the original Washington Post report.