That's the dilemma posed by red-light camera enforcement programs, which require substantial sums upfront to cover the cost of installing and maintaining cameras, as well as paperwork associated with issuing $100 tickets to motorists who fail to stop on red.

In Philadelphia, where 25 intersections have been equipped with cameras since 2005, the high volume of violations means the program's costs have been covered, and more. With an annual take of $10 million in fines, the cameras monitoring intersections from Center City to the Northeast spin off about $3 million extra for state and city coffers after expenses are deducted.

But in Abington Township, where officials plan to install cameras at three dangerous intersections along Old York Road and on Moreland Road, the numbers may not tally so easily due to the lower volume of traffic.

Two weeks ago, the AAA Mid-Atlantic office warned that the township would need to issue 5,040 violations a year to cover the anticipated costs of the red-light cameras. That would exceed the total tickets issued at one of the city's busiest corners — at Roosevelt Boulevard and Grant Avenue — said AAA.

Although the contractor on tap to run Abington's program in its first year has stated it would not charge the municipality if fines fail to cover costs, the AAA calculation raises the prospect that township officials eventually could be faced with deciding whether to subsidize the cameras. Would the payoff in public safety be worth it?

If fines fail to keep pace, township officials and taxpayers should demand a clearer understanding of whether camera-equipped intersections are keeping motorists safer than might be done with other, less-expensive traffic-safety measures.

In general, the jury is still out on red-light cameras. Advocates point to communities where accidents and violations have been reduced. But Philadelphia police two years ago reported an increase in accidents at camera locations, and some national studies have produced inconclusive findings.

At a minimum, officials in Abington and other communities considering traffic cameras should pledge to first take a candid look at the hard costs as well as the purported safety benefits from snapping speeding motorists' portraits.

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