A guilt gradient in the illegal use of parking spaces reserved for people with disabilities: field observations over five years.

Three parking spaces clearly designated as reserved for people with disabilities were observed from 8:00 AM until 9:00 PM on Monday through Saturday of the second or third week in November for five consecutive years. During the seven weeks of observation, 962 drivers parked illegally in those three reserved spaces. Informal observations and previous research suggested that illegal parkers would be more likely to park in the least conspicuous parking spaces, and, as predicted, a significant monotonic relationship was found. Thus, the data generally agree with the prediction that illegal parkers in spaces reserved for people with disabilities are less likely to park in the more conspicuous parking spaces and are more likely to park in the least conspicuous parking spaces, suggesting a guilt gradient in this illegal parking.