By James F. Kenney

The violent assaults on innocent bystanders in Center City by packs of roving youth have taught us one thing: our best defense against violent mobs must be a strong offense.

Adding to efforts already in place, Philadelphia should move quickly to establish a part-time paid reserve police unit, made up of recently retired city police officers.

This reserve unit would supplement Police Commissioner Charles Ramsey's crime-fighting plan and "anti-flash mob" efforts in Center City and other neighborhoods and business districts - including Main Street in Manayunk, 52d and Market Streets, and Passyunk and Frankford Avenues.

Currently there are 6,637 uniformed officers on the force. We could supplement that force with an estimated 800 retired officers between the age of 45 and 55 who could serve as a pool for a reserve unit.

The average pension for a recently retired 20-year officer is $24,240 a year. Since retired police officers are not permitted to collect Social Security, most rely on part-time work to help make ends meet.

Using the call-up of reserve military personnel during national emergencies as our model, reserve officers would be in uniform, under the direct control of the Police Department, and paid on a per-hour basis. Private funding should be explored to help fund this unit.

To implement this program, legislation would be needed to eliminate the prohibition that keeps city employees from getting paid by the city while simultaneously collecting a city pension.

Mayor Nutter and Commissioner Ramsey are to be commended for moving quickly to increase the presence of uniformed police in Center City to combat flash mobs, while also instituting and strictly enforcing a 9 p.m. curfew for teenagers under 18.

Under Ramsey's leadership, violent crime in Philadelphia is at its lowest since 1979. The commissioner implemented a major restructuring of the department with increased visibility of uniformed patrols as the core of his crime-fighting strategy. He employed smarter deployment of personnel, and increased the use of new technology - as well as implementing a comprehensive and thoughtful anticrime strategy.

Inquirer columnist Karen Heller recently summarized some of Ramsey's innovative approaches: creation of "a new shift, 8 p.m. to 4 a.m., when most violent crime occurs. Ramsey long ago got the cops out of cars, on their feet and onto bikes, making them active participants in the neighborhoods.

"Now the force relies more on cameras and statistics. Academy standards have been raised, a minimum of 60 hours college credit. The department's plan, like any business plan, lists strategic objectives, almost 150, and a progress report on earlier goals."

Coupled with Ramsey's efforts, are those of Common Pleas Court Judge Kevin Dougherty and other members of the judiciary who are to be commended for taking a hard line against flash mob assailants.

Concrete law-enforcement steps, coupled with severe penalties, should send a strong message to would-be flash mob assailants - and their parents.

While there is an ever-increasing cost to taxpayers for this added police protection, the stakes are too high for the city not to do all it can to combat lawless intent.

Thousands of jobs in the restaurant, hotel, and retail industries are at risk if these attacks continue - causing residents and tourists to fear coming to Center City.

It took a lot of hard work, vision, and money over many years to make Center City the robust, and vibrant social, cultural and entertainment mecca that it has become for thousands. We can't allow a few violent criminals to destroy all that hard work - and all those good-paying jobs.

While establishing a reserve police unit of retired officers will require some changes in city law, as well as union negotiations, I believe a supplemental force will not only help combat and stop flash mobs, it will also add a critical component to the fight against crime in city neighborhoods.