In Australia drivers can be reported by other drivers for littering, which I LOVED. All you had to do was to fill out a report stating what you saw, the time/location and the license plate number of the pig who threw the trash out of the window. The witness had the option to agree to appear in court should the pig contest the allegations. If the litterbug did contest, the police would call the witness to see if s/he was willing to testify in court (under oath) against the litterbug. The litterbug then had two options: either pay the $250 fine straight up or go to court and risk paying a $1,000 minimum fine. LOVED it!