This weekend, the New York Times released a blockbuster investigation showing how defense contractor Raytheon successfully persuaded the Trump administration to continue arming Saudi Arabia in the war in Yemen, even as civilian casualties increased and it became clearer that supporting the war further undermined the U.S.’s interests in the region.

The Times’s reporting raises a number of questions that Congress should investigate, including whether the State Department has been improperly sidelined from national security decision-making, whether advancing arms sales has undermined other national security interests, and whether former State Department officials’ ability to become influence-peddlers for arms dealers undermined the diplomatic mission of the department.

It now appears that State Department Inspector General Steve Linick’s office was conducting a similar investigation into the president’s declaration of a national emergency to support Saudi arms sales. But while the Times investigation is likely to garner the reporters well-deserved awards, Linick seems to have been rewarded by the president firing him last Friday night due to a “loss of confidence.” It quickly became clear his removal was at the request of Secretary of State Mike Pompeo.

It also seems that the administration was unhappy with Linick’s probe into whistleblower allegations that Pompeo had misused government resources by asking staff to perform personal tasks for him and his wife, including walking their dog and making restaurant reservations.

For those unfamiliar with inspectors general (IGs), they are independent federal watchdogs who conduct investigations into fraud and abuse, and report their findings to both to the executive branch and to Congress. Congress has made clear from the beginning that exposing embarrassing actions by the executive branch would not be sufficient justification for removal.

If Linick was removed in retaliation for the Saudi arms sales investigation, which had been initiated at the request of House Foreign Affairs committee Chair Eliot Engel, it’s a devastating strike at Congress’s core constitutional duties to conduct oversight as a co-equal branch of government. It also undermines the independence of inspectors general at a moment when government misconduct is reaching pandemic proportions.

The president can remove an IG, but over the years Congress has increasingly restricted the conditions under which he can do so, including requiring that the president provide Congress with his reasoning. In this case, a number of congressional leaders have accurately pointed out that “loss of confidence” isn’t an appropriate justification.

Congress must enact lasting reforms that make it undeniably clear that inspectors general can only be removed for cause. But in the interim, Congress needs to hold this administration accountable.

This is not to say it isn’t sometimes necessary to remove inspectors general. But removal without justification isn’t acceptable. Congress has demonstrated several models of how to properly hold failed watchdogs accountable. A probe from the Senate Homeland Security and Governmental Affairs committee resulted in the resignation of an acting inspector general who had become too cozy with the agency he was overseeing and a House Science committee investigation into to a Commerce IG who abused his position similarly persuaded him to resign.

Yet now, Congress is reaping what they sow in insufficient responses to recent firings. The removal of Michael Atkinson, the intelligence community inspector general, should have led to a strong bipartisan rebuke, including congressional investigations and hearings about that decision. While there was a bipartisan letter asking the president to provide more of an explanation for that firing, there were no consequences when the president failed to respond. It’s clear that this letter wasn’t enough to warrant a response, let alone deter the president from removing principal deputy defense inspector general Glenn Fine, acting Transportation inspector general Mitch Behm, or of course, Linick.

The House Foreign Affairs committee and the Senate Foreign Relations Committee are taking the right step now by opening an investigation into the removal. But this should only be the beginning. Their work should include continuing the investigations the IGs were not able to complete, one of many overdue steps for Congress to reassert itself as a coequal branch in foreign policy.

They also need to get the attention of the executive branch. The executive branch’s move to thwart an investigation into arms sales is a four alarm fire that should not be ignored, and those committees should use their power to halt weapons sales until the administration provides them with the information and documents they need to do their work. These events also make a compelling case for Congress to strengthen its own oversight power under the Arms Export Control Act. It’s bad enough that the arms industry is jeopardizing the health and safety of their workers to further arms sales abroad. The Secretary of State putting the checks and balances of our Constitution at risk to line the pockets of the defense industry is inexcusable.

Oversight and accountability are under attack right now. Congress needs to step up to defend its own oversight power and inspectors general, who are one of the most powerful tools Congress has to hold this administration and future ones accountable.