Andrew Wheeler during his confirmation hearing to be deputy administrator of the Environmental Protection Agency. (Alex Edelman/AP)

The Environmental Protection Agency did not violate the Hatch Act, which seeks to keep government functions nonpartisan, when it appeared to criticize the Democratic Party after a confirmation vote in April, the federal office that investigates such matters recently found.

The message that sparked the inquiry came April 13 from the EPA’s main Twitter account, shortly after former coal and nuclear lobbyist Andrew Wheeler was confirmed by the Senate to be the agency’s second-in-command. Wheeler was voted through 53 to 45, with the vast majority of Senate Democrats opposing his nomination.

AFGE Council 238, a union that represents EPA employees, later filed a complaint about the tweet, alleging that it violated the Hatch Act of 1939, which prohibits federal employees, except for the president and other high-level officials, from using government resources to support political parties or partisan candidates.

But in a letter to an EPA ethics official dated May 23, the U.S. Office of Special Counsel said that it had found no such violation and that it would be “closing our file without further action.”

The office noted that there was no evidence that EPA Administrator Scott Pruitt composed the tweet or directed anyone at the agency to post it. In addition, the letter states, the tweet didn’t amount to a Hatch Act violation because “it was not aimed at the electoral success or defeat of a political party or candidate for partisan political office.”

Despite the conclusion of the Office of Special Counsel, the controversy over the tweet hasn’t gone away.

On Tuesday, Sen. Tom Udall (N.M.), the ranking Democrat on the Senate Appropriations subcommittee that oversees the EPA, announced that the Government Accountability Office had agreed to his request to produce a legal opinion on whether the EPA’s tweet violated a prohibition on the use of agency funds for publicity and propaganda.

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