Just my opinion, but hiring their own investigator allows the family to feel like they are doing something. It is a psychological control mechanism. While it works on that level, it will gum up LE's efforts, with having to shield items from their PI and ensure the PI doesn't tip off a POI, meaning the PI will be in their way. In short, it will make the family feel better, but creates other issues for LE. IMHO.I think the family has lost faith in LE.