Is my rear wiper legally required to operate?
Federal Motor Vehicle Safety Standards (FMVSS) specify that manufacturers must include rear wipers on all new motor vehicles sold in the United States. However, current FMVSS standards do not require that a passenger motor vehicle be equipped with a rear wiper on the road. In some states and jurisdictions, a vehicle equipped with a rear wiper must have one that is functioning. Other states have no legal requirements on rear wipers since they are not required in the first place. However, these laws vary from state to state so for further detail, please see state-by-state safety equipment inspection requirements.