If stealing a car from his mom wasn't bad enough, police say a Florissant man trotted out an extremely lame alibi: He tried to say he was actually returning it.The bizarre case began last fall when the man's mother told police he had taken her 1999 Chrysler 3000 from her home without permission. A St. Louis County police officer finally caught up to 44-year-old Rudy Boykins about three weeks later in December, according to court documents.
He was driving the missing car at the time, but he had an explanation, authorities say.…