I've always suspected the very same thing.
Clearly they can benefit from holding one over your head, in-case they ever come across a need to detain you for any period of time. Here's what
happened to me.
About 25 years ago, I got pulled over in my custom painted hot-rod, was told I made an "unsafe lane change", and was given a citation.
When I went to court, I noticed that my name wasn't on the "docket" for that day. I went to the clerk, and showed her the ticket. She told me that
I would have to get a hold of the agency that wrote it.
When I called the Sheriff's Dept, they told me that the officer who wrote me the ticket didn't work there anymore, and they didn't have his ticket
book. Over the next several weeks, I periodically called both the courthouse and the Sheriff's Dept. to see if they'd gotten a hold of him so I
could take care of the ticket, and to make sure I didn't have a warrant.
Fast forward 15 years.
Early Christmas eve morning, I jumped in my truck to go collect a check for a construction job I had just completed. Since I kept the work truck
parked in a secure garage, I always just left my tools in the back, and lots of them.
I collected my check, and started heading home. As soon as I pulled away from the curb, a sheriff got on my bumper, tailgated me down the road for
about a mile, and hit his red light, so I pulled over.
When he got to the window, he told me that the reason he pulled me over was because my truck matched the description of one that had been seen near
construction sites that were recently broken into.
I'm pretty sure this guy thought he had his man, and it was time to use that hole card.
Being so long ago, I don't quite remember the conversation, but I do remember the other two cruisers screeching in around me, blocking me in, like I
was trying to get away or something.
Of course, they ran me for warrants and, what do you know, I had one! (15 years old, for an unsafe lane change!)
Other than mentioning the reason for pulling me over, they never charged me with anything.
Embarrassing as it was, I called my dad and had him come bail me out of jail for the unpaid ticket. I didn't feel like spending Christmas locked up,
and it was a weekend so there wouldn't be a chance to see a judge before then.
Now, I know for a fact my name had been run 3 times during those 15 years, the most recent was literally 3 days earlier when I was held hostage by a
murderer that decided that my house looked like a good place to hide. Hell, after I escaped, they had me handcuffed in the back of a squad car while
they killed him wearing my clothes. (another story altogether)
So what are the odds that warrant came out of nowhere when it did? Why not a few days earlier? Why not a few years earlier?
Anyway, when I went to get my truck out of impound that day, they told me I'd have to come back later for it. I went home, enjoyed my Christmas and
went back to get it the following Monday.
Turns out, the reason they wouldn't give me my truck was because they were busy doing a complete inventory on every item in it and checking every
single serial number on all my equipment. They handed me an itemized list, several pages long, complete with a detailed description of every thing I
owned, which I have to this day since I still have many of those tools.
After all that, I showed up to the re-scheduled court date and paid the $80 fine.
Right after I rolled my eyes at the judge like this.