As police fuckers go, this is relatively benign, I guess, but it just goes to show you how petty and pointless cops and their boosters are:
NYPD Union Uses Flickr in Innovative New Push to Shame the Homeless
Also, I'll just point out that on the pictures with EXIF data, you can search on the individual camera IDs and often identify the owner.
Spoiler! Rich white tech industry boys with iPhones seem to be disproportionately represented. I'm guessing any cops doing this have been instructed in how to strip their identifying data.