> the burden of proof is probably on those who want to refute this claim.

I agree that the claim is fairly self-evident, but the burden of proof should be on the person making the claim.

It's not my job to do your research!

> but the burden of proof should be on the person making the claim.

I think the burden of proof should be on whomever is making the less collectively accepted claim. If I claim the earth is round and you are a flat earther, I don't have to prove anything to you despite your demands. However, if people everywhere generally accept that the earth is flat, then indeed the burden of proof is on me to prove that the earth is actually round.

In GP's example, the statement "as long as there are criminal opportunities, some percentage of baseline humans will want to exploit them" is a collectively accepted claim. Therefore the burden of proof is on anyone claiming something to the contrary.

> I think the burden of proof should be on whomever is making the less collectively accepted claim.

Good point

There's a great deal of difference between a generally verifiable claim, supported by thousands of years of human history, and a request for specific citations of scientifically-validated studies.

In this case, it is your job to do research. This isn't a research journal, it's a discussion board. If you want to deep dive into a topic brought up on the board, it's your responsibility to follow up, not the OP's.