alt Hacker NewsYeah that sounds basically impossible to prove since the onus is on them to prove the negative that you never consented to it, but my guess is since it's a civil ticket it goes through some kangaroo court where you are fucked from the get go and the judge is basically the 21st century equivalent of a red-coat.
Owner's authorized agent sounds like a court would expect to see some sort of paperwork authorizing the placement of the graffiti. So when you say I told them it was ok the burden of proof falls on you that you did.