The Government Accountability Office said Trump substituted his own policy priorities over those enacted into law by Congress.

WASHINGTON President Trumps White House decision to withhold vital military assistance to Ukraine violated U.S federal law, a Congressional watchdog announced Thursday morning.
The Government Accountability Office, a non-partisan federal watchdog, noted that Faithful execution of the law does not permit the President to substitute his own policy priorities for those that Congress has enacted into law. And yet, the GAO found that was precisely what President Donald Trumps White House did.
The White House quickly shot back at the GAO, saying that the charge was an attempt by the watchdog to insert itself into the medias controversy of the day, according to the Washington Post.
The announcement will pour gasoline on the raging fire of Trumps impeachment, which just arrived in the Senate for a trial that will begin next week. The House impeached Trump in December for abusing his office by pressuring Ukraine to announce an investigation of his 2020 Democratic rival, former vice president Joe Biden.
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Trump withheld $391 million in aid to Ukraine in July of last year in what Democrats argue was a pressure tactic to get Ukraine to announce the investigation. The White House tried to argue that that was standard operating procedure.
But in July, Trump personally asked Ukrainian President Volodymyr Zelensky to look into former Vice President Joe Biden and his son Hunter, whod previously sat on the board of a Ukrainian energy company.
Emails that were made public in December show that Trump directed his budget office to withhold aid to Ukraine less than two hours after Trump got off the phone with Zelensky.
The GAO found in its report that the White House had violated the Impoundment Control Act, which lays out the specific mechanism through which the executive branch can request that Congress reconsider the way its allocated funds.
Cover: U.S. President Donald Trump speaks in the East Room at the White House, on January 15, 2020 in Washington, DC. (Photo by The Asahi Shimbun via Getty Images)