When defending the heavy focus on curfew sweeps in neighborhoods like City Heights, a tactic we've been exploring lately, proponents often say that most violent crime happens during curfew hours.
The community needs the sweeps, residents, police and politicians say, to physically remove kids from a dangerous environment so they won't become victims or perpetrators of crime.
However, we crunched the numbers and, as the graphs above show, most juvenile crime in San Diego actually happens outside of curfew hours.
Contrary to proponents' claims, the number of juvenile arrests have typically peaked around 10 a.m. and the number of juvenile victims of violent crime around 3 p.m. After those peaks, crime has tended to gradually fall until the early morning hours.
These trends are a main reason why Dan Macallair, executive director of the Center on Juvenile and Criminal Justice, argues against curfew sweeps. He studied curfews in California more than a decade ago and came to the conclusion that they had no significant impact on crime.
When I called him for a recent story about San Diego's curfew sweeps, Macallair said police here were making a fundamental mistake. Sweeps don't reduce juvenile crime because they don't address when most of the crime occurs, he said.
"It's a bad use of police resources," Macallair told me. "You've taken that police officer off the street for about an hour. They're not responding to more serious calls."
Dozens of residents, social service providers, police officers and other law enforcement officials participate in San Diego's monthly sweeps. Police say officers usually work the sweeps as part of their normal duty but they have sometimes received overtime pay.
I've heard claims about when juvenile crime hits its peak from the program's proponents for years, but one instance stands out because it came during an emergency meeting with the City Council and from a high authority on crime trends.
In February 2010, a federal court struck down San Diego's curfew law. Rather than fight the ruling, police asked the council to immediately approve a new, less restrictive law. Without it, police told the council, no curfew would be enforced and crime might rise.
"We feel very strongly that this is an ordinance that's helped us reduce violent crime against juveniles," Asst. Police Chief Boyd Long, who oversees patrol operations, told the council. "The city of San Diego believes and the data can prove that the violence starts at around 10 p.m. at night."
Long didn't provide any statistics at the meeting to back up the claim and none of the council members asked for it. They only discussed a few procedural issues, praised the value of San Diego's curfew sweeps and then unanimously approved the new law.
Proponents have long said the sweeps prevent kids from becoming victims or perpetrators of crime. Police have attributed a recent decline in violent crime to the sweeps and warned that crime might rise without them.
However, our in-depth analysis of crime data earlier this month questioned that connection. Neighborhoods without the sweeps have reported greater drops in crime than those with them. While curfew arrests fell statewide and climbed in San Diego, statewide law enforcement agencies reported equal or better results than San Diego police.
