I was in an accident last year. It wasn't deadly, but it did
cause paint damage to the passenger side. A cop even filed a complete
report.

Yesterday, I inputted my VIN in carfax and carfax came back with a full
report saying my car had never been in an accident.

My point is, how can I find carfax reliable if it didn't even
report that my car was in an accident?

Since I'm using carfax to check on another vehicle that I want to
purchase, how do I know that the information regarding the other
vehicle is accurate?