Legal analysis of the Ukraine controversy has so far focused on whether President Trump’s July 25 call with Ukrainian President Volodymyr Zelensky involved extortion, bribery or solicitation of an illegal campaign contribution from a foreign source. But as the House investigation has proceeded, a more straightforward legal case has emerged: The president, and possibly other officials, may have violated the Hatch Act’s civil and criminal prohibitions on the use of executive branch powers for partisan ends.

As the recent testimony of acting ambassador William B. Taylor Jr. — among other evidence — makes clear, State Department officials and other government employees were enlisted in the effort to persuade Ukraine to investigate former vice president Joe Biden and his son Hunter. As Taylor put it in a Sept. 9 text to the U.S. ambassador to the European Union, Gordon Sondland, the goal appeared to be to use the levers of U.S. policy to extract Ukraine’s “help with a political campaign” — Trump’s campaign for reelection.

An enterprise of that sort emanating from the Trump White House, if proved, would be the very kind of activity the Hatch Act was designed to prevent. The text of the law flatly states that an employee of the executive branch may not, among other things, “use his official authority or influence for the purpose of interfering with or affecting the result of an election.”

This prohibition has been part of federal law for more than a century. President Teddy Roosevelt used very similar language in an executive order he issued in 1907, modeling it, in turn, on a civil service rule dating to the administration of Chester A. Arthur. In 1939, Congress codified the strictures in the Hatch Act after an investigation confirmed that officials in Franklin Roosevelt’s Works Progress Administration had promised jobs and promotions in exchange for votes.

As spelled out in federal regulations, the Hatch Act bars a federal employee from “using his or her official title while participating in political activity” or “using his or her authority to coerce any person to participate in political activity.” “Political activity” is defined as “an activity directed toward the success or failure of a political party, candidate for partisan political office, or partisan political group” — which, of course, would include activity directed toward the success of Trump’s reelection campaign or the failure of Biden’s presidential campaign.

In general, violations of the Hatch Act are pursued civilly by the Office of Special Counsel, an independent federal agency; punishment can include firing or suspension without pay.

Importantly, the president and vice president are exempt from the Hatch Act’s civil restrictions on political activity. But that’s not the end of the matter. The Hatch Act also includes criminal prohibitions that apply to everyone, including the president, and at least two of them are relevant to the investigations surrounding the Ukraine matter.

Title 18, U.S. Code, Section 610, makes it a crime — indeed, a felony, punishable by up to three years in prison — for “any person to intimidate, threaten, command, or coerce, or attempt to intimidate, threaten, command, or coerce, any employee of the Federal Government . . . to engage in . . . any political activity.” Congress enacted this statute in 1993, amending the Hatch Act to provide “additional protections against political manipulation of the federal workforce,” as a 2017 Justice Department publication put it.

In short, the president and his aides cannot commandeer the federal bureaucracy in service of the president’s purely partisan political objectives as a candidate for office. Notably, Section 610 does not require a “quid pro quo,” nor does it require that the object of the political activity constitute a “thing of value” — conditions required to demonstrate extortion, bribery or violations of campaign finance law. If Trump commanded, coerced or intimidated State Department officials or other federal employees to engage in impermissible political activity — or attempted to do so — that would be a criminal violation of the Hatch Act. (This would also be true for other top officials who recruited government employees for the effort.)

The available evidence suggests that, on orders of the president and his acting chief of staff, career diplomats at the State Department were shunted aside to pave the way for an effort to push Ukraine to investigate Burisma Holdings (the company where Hunter Biden served as a director) and supposed Ukrainian interference in the 2016 election. Sondland and special envoy Kurt Volker allegedly proceeded to press Ukrainian officials to do just that, using the promise of a White House meeting and, later, the release of much-needed military aid as inducements.

According to Taylor, Sondland said the president “did insist” and “was adamant” that Zelensky publicly commit to these investigations and assigned Sondland to convey that message to Zelensky and a top aide, Andrey Yermak. Sondland repeatedly emphasized in his testimony that the president “directed” him to allow Rudolph W. Giuliani, Trump’s personal lawyer, to guide those efforts and that he understood Giuliani to be “expressing the concerns of the president.” (On Wednesday, the nonpartisan Project on Government Oversight asked the Office of Special Counsel to investigate potential Hatch Act violations by Sondland and acting White House chief of staff Mick Mulvaney — and the group argued that Trump could be implicated as well.)

There’s another Hatch Act-related offense that may have been committed. Under Title 18, U.S. Code, Section 600, which was part of the original Hatch Act, it is a crime for anyone to promise a benefit made possible by an act of Congress as “consideration, favor, or reward for any political activity or for the support of or opposition to any candidate or any political party” in connection with an election. According to the Justice Department, Section 600 is triggered when “corrupt public officials use government-funded jobs or programs to advance a partisan political agenda rather than to serve the public interest.” Although a violation of Section 600 is a misdemeanor, the Justice Department says that in egregious cases it could support a felony charge of conspiracy to defraud the United States (by interfering with the fair and impartial administration of a federally funded program).

In other words, if the president or other officials tied the receipt of congressionally authorized military aid to Ukrainian help for the president’s reelection campaign, that too could constitute a criminal offense. Such a scheme would echo a Nixon White House effort, dubbed the “Responsiveness Program,” to channel federal grants and contracts to groups or individuals who promised to support Nixon’s reelection bid. The Senate Watergate Committee’s report concluded that this diversion of taxpayer money from its intended use “to the political goal of reelecting the President” probably involved a criminal violation of the Hatch Act and a criminal conspiracy to defraud the United States.

So far, the Ukraine inquiry has focused on whether Trump improperly, or even illegally, solicited “foreign interference” in the 2020 presidential election. But the possibility that the president illegally directed improper election interference by U.S. officials is at least as disturbing, and it ought to be examined as part of the House investigation.