Teenagers in my city are targeted for fines as they're without the resources to fight unfair enforcement.
Ex: Install no parking signs on the streets surrounding the high school during the day and ticket all the students. Inform the students that they had a duty to move their cars upon installation of the signs as there is no grace period. Of course officers were standing by to write truancy tickets for any student who did.
Subtext: Begin requiring paid permits for the parking lot, which also require agreeing allow any property searches - waiving 4th amendment rights. Given that students whose cars were at home were singled out for searches because drug dogs alerted on their car (allegedly in the parking lot), it's clear why the considered probable cause an impediment.
In adult life, I use a dash cam because of the false traffic citations. The last one it saved me from was a 51 in a 40 zone ticket. I was driving 40, period - and have video. When I watched them afterwards, two patrol cars were literally ticketing the next car driving by after they finished writing the last citation.