I mean it's definitely possible. We hear CSAM and assume it's to do with obvious children, but it also includes 16-17 year olds and in that age range it's not always possible to tell the difference. That, plus the proliferation of self made pornography can make for something of a minefield. I'd bet my left arm that there's an uncomfortable amount of CSAM floating around on reddit or anywhere else that doesn't have a robust age verification process.

This guy is probably a scumbag, but it's also quite possible that he didn't actually know that the persons were underage. Be careful out there.

Well then that cop is just dumb. If you're going to disappear a gun from the evidence room, why would you disappear one from a school shooting and not one from some schmo with a drug arrest or whatever?

Ooh. Missed that part. Thank you!

It explains that the cop sold the guns to the CI. Unless the CI was the school shooter, the gun was then transferred at least one more time.

If the cops know enough about the initial buy to know what was said, how/why was that gun allowed to be transferred further?

How'd the gun get from the CI to the shooter?