The US asking another country to investigate a citizen

With Trump admittedly (I think?) asking the Ukraine to investigate Hunter Biden, I’m trying to think of other cases where an administration has asked another country to investigate the wrongdoing of a US citizen. I know we’ve asked for US citizens in other countries to be extradited to the US for prosecution here. I imagine there are cases where we’ve asked other countries for support to assist an investigation here, but that’s not the case here.

So, are there other cases where an administration has said, hey, you, other country, please investigate this US citizen?

Good question.

And this is irrespective of whether or not the US citizen is a relative of the “asker’s” political rival. Or whether or not the “asker” makes mention of witholding of millions of dollars in aid.

That’s correct, just in general. The idea seems so foreign to me, to ask another country to try and prosecute our own citizen. Seems like it’s our job to do that. I can’t recall us asked even regular justice systems like France, the UK, Canada, or Australia, let along a corrupt mess like Ukraine’s.

Sure, it happens all the time with cross-border crime, through Mutual Legal Assistance treaties. If Joe Merican is suspected by the FBI of cross-border smuggling into Canada, of course they’ll contact the Mounties and say “we think Joe Merican is smuggling stuff. Here’s the evidence we’ve got. Can you investigate to see if there’s evidence on your side of the border?”

But that’s done by law enforcement agencies, working with requirements like “evidence” and “probable cause” and all those other “technicalities” that police have to comply with.

It’s not the head of state calling the head of state of another country and saying “That aid we promised you? It’s not coming unless you charge my political enemy’s son with something”