Joseph Kallinger was a Philadelphia shoemaker whose 1974-1975 crime spree relied on his 13-year-old son as an accomplice. Kallinger was born in 1937 and was adopted into an abusive family. In turn, he was abusive to his six children and was arrested and imprisoned on child-abuse charges in 1972. Three of them initially testified against their father but then recanted. In the fall 1974, one of the three, Joseph Jr., was found dead in an old building in Philadelphia. Not long afterward, Kallinger and another son, Michael, broke into or gained entry into occupied homes to rob and terrorize their residents. In January of 1975, they posed as salespeople and beat eight people inside a Leonia, New Jersey home; one of them was taken to the basement and her throat was slit. A blood-stained shirt left behind was traced to the Kallinger home through a laundry mark, and police arrested father and son there.

At his trial in 1976, the elder Kallinger was diagnosed as paranoid and schizophrenic and pleaded not guilty by reason of insanity. The jury disagreed and convicted him for the Leonia murder; he was also convicted of murdering his other son and a nine-year-old boy from Philadelphia. He died in 1996 after a seizure, having spent the last five years of his life in solitary confinement under a suicide watch. His son, Michael, spent time in a juvenile facility, and later changed his name.