The legal memos, obtained by POLITICO, include an instruction that says: “Senate-confirmed Presidential appointees may not even attend a political party convention or convention-related event.” That sentence is one of the few to be bolded in the memo.

Pompeo is a Senate-confirmed presidential appointee, and the rules do not appear to make an exception for him. The rules also don’t appear to say that such appointees may attend a convention in their personal capacity.

In fact, in his email, Biegun notes, “In my case, as a Senate confirmed Department official, I will be sitting on the sidelines of the political process this year, and will not be attending any political events, to include the national conventions.”

In addition, the rules appear to be more restrictive for U.S. diplomats outside the United States than those on American soil.

If they are in the United States, the legal memo says, political appointees “other than a Senate confirmed presidential appointee” are permitted to attend outside of work “a partisan political rally, fundraising function, election party, meet-the-candidate event, or other political gathering as a spectator.”

Also permitted outside of work only when in the United States: “Attending a political party convention or convention-related event as a spectator, if you are a political appointee other than a Senate-confirmed Presidential appointee.”

Not only is Pompeo a Senate-confirmed appointee, his appearance will take place Tuesday night, while he is on travel to the Middle East.

The State Department did not respond to POLITICO’s requests for comment on this issue on Monday or Tuesday.

But unnamed department officials have told other news organizations, such as McClatchy, that multiple legal teams have signed off on Pompeo’s appearance, and that the secretary will be acting in his personal capacity without any assistance or resources from the State Department.

One potential loophole may be how the lawyers are defining the word “attend.”

CNN, citing an unnamed source, said Pompeo’s appearance will be “pre-recorded” and delivered from a rooftop in Jerusalem. Whether that qualifies as “attending” the event could be up for debate.

Traditionally, secretaries of State in both Republican and Democratic administrations have sought to avoid commenting on or being involved in partisan issues during their time at Foggy Bottom. The idea is that politics should be left behind so that American can speak with one voice to other countries.

But Pompeo has pushed the envelope on partisanship during his tenure. He has spoken at Republican-oriented events such as the Values Voter Summit and the Conservative Political Action Conference. He’s also spoken to a number of Christian organizations about the role Christianity plays in his life, moves that have unsettled many U.S. diplomats who worry about how this is perceived abroad.

Pompeo, a former GOP congressman from Kansas, is believed to be eyeing a future presidential run. He has engaged in an unusual number of trips within the United States, including to Kansas, where he flirted with the idea of running for Senate, and Iowa, a key stop on the presidential trail.

Pompeo has dismissed criticisms that he is politicizing his office, pointing to a watchdog report clearing him of improperly violating regulations governing officials’ political activity. Instead, he has defended many of these events as being a way to educate Americans about the work of the State Department, especially its promotion of such causes are religious freedom abroad.

The secretary of State’s appearance at the Republican convention also comes as he faces an ongoing inspector general’s investigation into whether he and his wife, Susan, have improperly used State Department resources for personal purposes.

Pompeo’s successful move to engineer the firing of State Department Inspector General Steve Linick amid this still-ongoing probe has led to more scrutiny about his role as secretary from Democratic lawmakers.