Counselor, I stipulate I'm not a lawyer.
You didn't say there was no PC, but at least one other poster did.
I appreciate the rationale you present re: protection of the 4th Amendment.
On the other hand, if the perpetrators' solution to imminent arrest for possession of illegal drugs or other contraband were to simply toss it out of the car window and clam up, then the law wouldn't make sense either. In this case, a little weed doesn't strike me as that big a deal. But I can easily envision harder drugs perhaps in greater quantity, or other contraband, that would be quite worthy of police interest and investigation (not misconduct.)
It frustrates me that these sort of matters get all knotted up in court at all. Judgment gets replaced by legalities. Here, I'll assume we eventually paid for 2-4 cops to investigate the scene, transport these kids to jail, house, feed and process them, prosecutors, judge, files, etc. etc. etc. It's an expensive process. And for what, here?
LP has an accountability structure (Muschamp) that will hopefully reinforce the proper boundaries, hold him accountable and gain a positive result for LP and society.
And "back in the day" a cop could exercise the judgment to remand a young person to the discipline of their family for something minor. Now, the cop has much less latitude to make that decision and it is much less likely that the young people have (or accept) that family-level correction. The substitute is an expensive phalanx of legalities surrounding the 4th Amendment.