I don't think the PPD representative misspoke or lied when he said the PPD has the right to investigate. Going and talking to someone and initiating a consensual encounter is different from detaining someone/performing a Terry stop. Unfortunately, the problem in those types of situations is in practice, people, both LEO and John/Jane Q. Public, frequently don't know/understand the difference between a consensual encounter and a detention/Terry stop.
As for OC making people a target, or being a deterrent I don't think there's enough evidence to make a case for either.