WASHINGTON (RNS) — A Muslim civil rights group, Jewish Democrats and members of Congress are alleging that a Republican National Convention address by Secretary of State Mike Pompeo, delivered from Jerusalem, potentially violated a law that bars certain federal employees from engaging in political activities.

The Council on American-Islamic Relations, a Muslim civil rights group, was among the first to sound the alarm about the prerecorded address, which featured Pompeo standing in front of a Jerusalem skyline at night and referring to it as the “city of God.” In the group’s written complaint, CAIR’s director of government affairs, Robert McCaw, argued that Pompeo’s speech may have violated the Hatch Act.

“As you are aware, the Hatch Act prohibits all federal employees in the Executive Branch, including the Secretary of State, from engaging in some forms of political activity,” the complaint read.

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“While spokespersons for the Department of State and Secretary Pompeo’s legal counsel have stated that no department funds or staff were used in Pompeo’s pre-recorded address to the RNC — the cost of the trip and visit itself is being paid for by the Department of State — while Pompeo strategically utilizes his presence in Jerusalem as a prop for partisan political gain.”

The Hatch Act, which was originally passed in 1939 and has been amended multiple times since, prohibits executive branch employees from “engag(ing) in political activity” while on duty. It also bars employees from doing so while in any room or building “occupied in the discharge of official duties,” while wearing a uniform or official insignia of their office, or using any vehicle owned or leased by the government of the United States.

Representatives for the State Department did not immediately return a request for comment.

CAIR was joined by U.S. Rep. Joaquin Castro, D-Texas, who said he had launched a formal House investigation into the speech.

“The Trump administration and Secretary Pompeo have shown a gross disregard not only of basic ethics, but also a blatant willingness to violate federal law for political gain,” Castro, who serves as vice chair of the House Foreign Affairs Committee and chairman of its Oversight and Investigations Subcommittee, said in a news release.

“It’s absolutely unacceptable that a sitting U.S. Secretary of State, America’s top diplomat, would use official taxpayer-funded business to participate in a political party convention, particularly after the State Department published guidance that explicitly prohibits such activity.”

It is unprecedented for a sitting secretary of state to address a party convention at all; Pompeo’s speaking slot shocked some former diplomats, who saw it as a breach of a long-standing policy of separating State Department work from electoral politics.

Halie Soifer, head of the Jewish Democratic Council of America, also decried the speech, calling it a “highly unethical” broach of the Hatch Act and part of what she called “the president’s ongoing effort to politicize the U.S.-Israel relationship.”

In his speech, Pompeo made reference to Trump’s decision to relocate the U.S. Embassy to Jerusalem in 2018, praising the president’s decision to move “the U.S. Embassy to this very city of God, Jerusalem, the rightful capital of the Jewish homeland.”

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The embassy shift, which was paired with Trump declaring Jerusalem Israel’s capital, proved divisive among religious leaders at the time: While many American evangelical Protestants praised the development, Christians in Jerusalem, the head of the Union for Reform Judaism, Muslim groups and Pope Francis all voiced criticism of the decision or its timing.

Soifer noted that Pompeo’s speech comes less than a week after Trump told a crowd that the Jerusalem decision was done “for the evangelicals.”

“Just last week, President Trump claimed that he ‘moved the capital of Israel to Jerusalem — that’s for the Evangelicals,’ demonstrating that he views U.S. policy toward Israel solely through a self-serving political lens,” wrote Soifer, who was previously a national security advisor to Sen. Kamala Harris. “By arranging for Secretary Pompeo to speak to the RNC while on official travel in Jerusalem, Trump is once again using Israel to score political points.”

Pompeo’s speech was one of several moments at the convention that Democrats and legal scholars argued could be considered Hatch Act violations. Observers noted that videos of Trump leading a naturalization ceremony and granting a pardon, which appeared to be filmed for the convention, could be considered examples of executive branch employees participating in political campaigning while operating in their official capacity.