In an attempt to combat theft on trains, Southern Pacific painted up a number of C-50-9 Class caboose with Police badges and lettering.
These were used on trains along with an SP Police Car pacing the train to deter people boarding trains and stealing or damaging lading and railroad equipment.
Along with the regular train crew, SP Railroad Police or Special Agents rode in the caboose to monitor the train.
The following are known from photos, but there may have been others.
The #4709 was heavily modified with spotlights and air-conditioners and painted white.
In December 1995 Athearn released a Special Edition set SE-2301 of two of their HO Scale C-40-4 caboose one depicting #4709 and the other #4766.
One other Police Caboose of interest was SP #01482 this was an ex DRGW caboose.
Microscale Decals has released a sheet #87-611 that has decals for the Police Caboose and the Police Passenger Coach.