Ultimately, the police are compounding mistakes made by Grogan, who apparently trusted his business partner so much that it took him more than four years to actually check the books and report anything stolen. Since the cars were goods for sale and not of any sentimental value to him, and he doesn’t need the money or he would have kept a closer eye on the business, the moral thing for him to do would be to leave the vehicles in the hands of their new owners and go after his former business partner for the money he effectively embezzled from the sales. That might not be legally feasible, though.
And even in cases where introducing a bias is desirable, you have to be very careful when doing it. There has been at least one case where introducing a bias towards diversity has caused problems when the algorithm is asked for images of historical people, who were often not diverse at all.