Question Posters and signs on car windows: Answers Are a fun way to personalize your vehicle. Are prohibited by state law if they obstruct a driver's view of the road. Are allowed only if they do not contain offensive language. Explanation Obstructions on windows are prohibited by state law. No sign, poster, or other material may be placed on any window of a vehicle if it obstructs a driver’s clear view of the roadway. Pass your DMV Written Test with flying colors Take me to the cheat sheet Alabama This questions appears in the following tests: Alabama Practice Test 31 Alabama Practice Test 14