Since the Senate acquitted President Donald Trump in early February, Trump has engaged in a campaign of removing those he feels are responsible for his impeachment and inspectors general who he thinks are Obama loyalists, firing four in the past two months. State Department Inspector General Steve Linick is the latest one.

Inspectors general serve as government watchdogs, investigating fraud, waste and abuse within the government. Created by Congress in the wake of the Watergate scandal to increase government accountability, they are appointed by the president and confirmed by the Senate. Inspectors general protect whistleblowers’ identity and largely work independently so they can investigate without fear of reprisal.

Linick, who was appointed by the Obama administration in 2013, was fired Friday night after launching an investigation into Secretary of State Mike Pompeo’s use of department resources to perform personal tasks. According to Rep. Eliot L. Engel (D-NY), he was also investigating an emergency declaration that allowed Trump to bypass Congress and sell weapons to Saudi Arabia. He will be replaced by Ambassador Stephen Akard, a close ally to Vice President Mike Pence, who served under Pence when he was governor of Indiana. Trump can fire any presidentially appointed inspector general, but is required to notify Congress ahead of any termination and provide a written explanation.

Democrats and some Republicans were quick to decry Trump’s decision to fire Linick. Sen. Susan Collins (R-ME) criticized him for failing to notify Congress or provide an appropriate justification for the firing. Engel has since joined Senator Bob Menendez (D-NJ) in launching an investigation into Linick’s firing.

Previously, Linick clashed with the president after releasing a series of reports outlining mismanagement and political retaliation against career officials in the State Department whom Trump appointees deemed weren’t loyal enough. He’d also played a small role in the House’s impeachment investigation when he provided the investigation documents related to Ukraine and the State Department that turned out to be largely inconsequential. By doing so, he broke ranks with other members of State Department leadership who’d vowed to not cooperate with the investigation.

Over the past two months, Trump fired three other inspectors general, starting with the Inspector General of the U.S. Intelligence Community, Michael Atkinson. Atkinson was fired after Trump’s acquittal, where he’d facilitated the whistleblower complaint that led to the impeachment proceedings. A few days later, Trump fired the Department of Defense’s Acting Inspector General, Glenn Fine, who had just been nominated to become the chairman of the Pandemic Response Accountability Committee tasked with overseeing the $2 trillion COVID-19 stimulus package. A day later, he fired Christi Grimm, the Inspector General of the Department of Health and Human Services, after she released a negative report detailing how unprepared the U.S. government was in its coronavirus response.

The firings, experts worry, could threaten the system of oversight inspectors general uphold, especially if they believe they might be retaliated against for failing to follow the president’s will.

"In each of these cases, the inspector general has done exactly what he or she was supposed to do, which was to serve in a nonpartisan way and to report honestly about shenanigans going on in the executive branch," former National Security Agency Inspector General Joel Brenner told MSNBC. "The president is not just attacking several IGs, he's attacking the entire institution of inspectors general."

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