Here's something that means nothing too from Brian's site.
On the bottom of the first page are 4 numbers: 4897 (?) with blue shirt written under it.
My late husband was a LEO. The rank and file called management "suits", senior officers were "white shirts", and regular officers were "blue shirts", provisionals or temps were "brown shirts". The numbers could be a shield number from someone in PD, FD, EMS, etc.
Could be. You never know. I always take stuff like this with a grain of salt AND an open mind.