Philadelphia's murder rate now tops U.S. cities with populations of more than 1 million. Statistics show that the biggest single cited cause of homicide was "arguments." Jerry Ratcliffe, chair of Criminal Justice at Temple, believes that's why the violence has been so hard to curb. "Causal factors are difficult to determine when the cause of so much homicide is not necessarily the economy or the drug trade, but the simple fact that two people are unable to settle a dispute in a non-violent manner."