No idea.  

Once you take the packages into your home, though, there's at least an argument that you've accepted responsibility for them, and have some duty of care to the addressee.  If you leave them outside, and don't accept delivery, you shouldn't have any responsibility.

Generally, before disposing of abandoned property, you have to mail a letter to the last known address (which in this case, is probably yours) letting them know of your intent to take possession, among other things.  However, there are all kinds of rules about specific items, etc.

If UPS won't help, you're best off contacting the company that's sending the stuff, and asking them to stop. 

You'll be good. It's UPS' responsibility since they either left it at your door step, without having it signed for, or had you sign for it despite you not being the person it was intended for. UPS will have no choice, but to reimburse the company for the lost goods, as the company will have to reimburse the buyer. It's like a trickle down effect.

As for any criminal action, you'll be fine. Nothing can be proved that you accepted the packages with intent to defraud any party (buyer, UPS, seller). The only thing that could occur is the buyer attempts to sue you civilly, but that's a real stretch And if it does occur, simply keep all documentation of your attempts to notify all pertinent parties (phone records, e-mails, etc.). In addition, the buyer has no chance of getting anything from it since there is no way of knowing if you discarded the items or not.

just curious, but what type of products are they? i know u dont know specifically bc u dont open them, but what type of company is it?  just curious, as i read.

roy and eddie answered it the way i would have.