House lawyers said in a filing Wednesday that President Donald Trump is currently acting “above the law” in his attempts to “obstruct his own impeachment” by barring witnesses from testifying before various committees.

According to Politico, the filing pertains to the lawyers’ months-long attempt to compel former White House lawyer Don McGahn to testify after the White House ordered him not to.

Though that aim is tied to the Russia scandal, the lawyers said that his behavior applies to the Ukraine one as well.

“If the President could deprive the committee of information required for its impeachment inquiry into his own misconduct, the President could potentially thwart his accountability for that conduct,” they wrote. “No further discussion will resolve an impasse dictated by the President himself.”

Trump’s administration has tried to muzzle multiple witnesses in the unfurling Ukrainian scandal with varying levels of success. Some, like former U.S. special envoy to Ukraine Kurt Volker, dismissed the administration’s warnings and testified anyway.