
Meanwhile, in the Antipodes
Not sure if our legislative setup is a little different to the UK, but in Oz the RSPCA Inspectorate have extensive legal powers similar to police, such as entry to property; search & seizure; gathering of evidence and powers to file criminal prosecution.
Public perception must be very different as well. The RSPCA is widely respected here. Not so aggressive on the political lobbying side, but they work directly with primary producers to certify the use best practices for humane treatment of animals/livestock, such as certifying that "Free Range Eggs" are exactly that.
The RSPCA Inspectorate can get access to police records, but the legislation in most states means that they practically are coppers anyway.