Saw a couple of online snippets about this track that ignore the obvious. Any literate person can tell this is another political / anti-govt ditty; not a safe sex anthem. And it's clearly not about the current Commander in Chief. Clues:

1. The U.S. President's vehicle (except under hated Bush II when they couldn't equip a Cadi with enough armour) has for decades been “Cadillac One” like the aeroplane.

“I know he got a big ol' cadillac,...
Pretty soon he'll have to take it back,...

2. The only or primary “bill” folks pay at City Hall are “taxes.”

3. The most prominent portrait at city hall is usually the POTUS—if he's the same party as the dominant party in the jurisdiction. (Republicans sometimes omit Dems from the pantheon in city buildings and schools just as Democrats pretend GOP Commanders in chief don't exist; it's super petty but all too common.)

I went to pay a bill at city hall...
And I seen his picture hanging on the wall”

4. A few folks online want to pretend this track is about Trump. Their entitled to their own delusions, but this was a 1982 piece, apparently recorded when Reagan was POTUS. Reagan is the only other POTUS Prince mentioned by name in songs (twice: Ronnie Talk to Russia, and Annie Christian). He penned a paean to Donald Trump long before he was elected, but he clearly didn't hate the man (“Donald Trump Black Version”) the song suggests he may have liked him as a person. Prince referred to Obama in Lavaux, a bit dismissively and when the Obamas invited him to the WH, he reportedly charged them a pretty penny and didn't do it for free.

“'Cause it took a BLACK FACE to see the same decay
...in the sun they'll melt away”

— Lavaux

5. The fact that he didn't name any POTUS in DLHFY suggests he meant all of them, regardless of party. So, it is about Trump, but not trump derangement syndrome so many folks suffer, since even Prince couldn't have predicted Trump before Prince “got suicided.”

[Edited 11/27/19 22:38pm]

Nobody has ever said this song is about Trump because... obviously it wasn't.

The people just aren't ready for "Donald Trump (Black Version)".

appleseed said:

“'Cause it took a BLACK FACE to see the same decay

.

Surely it was about Justin Trudeau

WhisperingDandelions said:

The people just aren't ready for "Donald Trump (Black Version)".

I think they are. Kanye West is still doing well.

Uhh... is this supposed to be a serious discussion? lol It was written in 1982 and it is plainly about some no good man wanted by the law... the picture hanging at city hall is a wanted poster "...the FBI is lookin' for his ass."