Other mistake: When Sarah puts Marty on the bus on his way home he steps onto the first step and turns to face Sarah as the door closes and the bus departs. It is against the law in California for buses to begin moving until passengers are on the main deck of the bus (one step up from the boy). This law was enacted after a child fell from the entry step of the bus (exactly where Marty stood), the doors opened and they were run over by the bus. California operates a zero tolerance policy on this matter; drivers know that a single infraction will result in the loss of their commercial drivers license and is taken very seriously by all drivers, without a single infraction having been reported in years.
OneHappyHusky
21st Oct 2008