Presence of other drivers as a determinant of traffic violations.

Nine hundred and sixty drivers (half of them women), who were first in line or in the first row, while waiting at an intersection, were observed as to whether they started to cross the intersection before the onset of the green light, in four situations. The smallest proportion of traffic law violators was found among the single drivers, while the largest one was among drivers surrounded by other drivers. Women tended to be less affected by the presence of other drivers than men.