The Senate committee handling the nomination of Ronald D. Vitiello to be head of Immigration and Customs Enforcement delayed its vote Wednesday, the Washington Post reported, because, among other things, he had shared “an image of Trump on Twitter that compared the president to a cartoon character Dennis the Menace.”

Vitiello sent the fateful tweet in March 2016, when Trump was ahead in the Republican primaries but as many across the country still didn’t take his candidacy seriously. Vitiello’s account has since been taken private.

Sen. Ron Johnson, the chairman of the Homeland Security and Governmental Affairs Committee, said in a letter obtained by the Post that the committee still had to do more “due diligence” on Vitiello following a letter from a group of unions representing ICE employees that included a number of potential issues that gave them “serious concern” about Vitiello, including the cartoon, which shows both Trump and the lovable scamp shrugging.

The letter from the ICE unions, obtained by the Post, says the tweet shows “at best …extremely poor judgment” and that “we are concerned with what appears to be a political statement against the now President and the possibility that this Tweet represents Mr. Vitiello’s true feelings about the President and his plans for the agency.”