But Resnick and several high-ranking police and parks officials all stressed that police and parks have been working together like never before.
Police officers regularly stop into recreation centers, hang around public pools and rec league games, and hold safety meetings with Parks and Rec staff.
"We're trying to be strategic in these times of limited resources," Resnick said.
Deputy Mayor and Parks Commissioner Mike DiBerardinis also said the department would spend about $375,000 in the fall to outfit 30 rec centers with surveillance cameras, which have proved to deter bad behavior in some of the city's largest rec centers in South and Northeast Philadelphia.
The summer's most frightening incident - the alleged rape of a 12-year-old girl in a stairwell at the Francis Myers center - happened during normal hours at a busy and active rec center.
Officials are compiling a report that would identify areas of rec centers where cameras would be most useful, as well as remote sections of buildings that would be best closed off.
But some of the other crimes this summer have happened in the off-hours, involving adults freely congregating in the city's public spaces. Last week, for instance, a man opened fire about 9:45 p.m. in the Wister playground - in Bass' Eighth District - wounding three other men.
Resnick compared those crimes to the shooting on the Benjamin Franklin Parkway during the city's enormous July Fourth Welcome America celebration.
"Hundreds and hundreds of police officers and some idiot pulled out a gun and started shooting," he said. "You just can't account for that kind of behavior."
Thursday's four-hour hearing was informational - no legislative action was taken - and Bass called it the start of "a dialogue" on the safety of parks and recreation centers.
Bass said one key was to get communities involved in their local parks and rec centers. Several witnesses already involved in their neighborhoods asked for something else - more money from the city.
In the recently passed budget, Bass said, "there just wasn't an extra dollar to squeeze."
"We want people to come out and participate. If people don't feel safe, they won't," she said. "We need to find ways to work with what he have and get people engaged."
Contact Troy Graham at 215-854-2730, firstname.lastname@example.org, or follow on Twitter @troyjgraham.