DALLAS—Dallas in late August joined a growing number of cities that are requiring convenience stores to boost security in an effort to curb criminal trespassing.

The Dallas City Council passed a series of rules designed to keep C-stores safer and give police the power to arrest trespassers and loiterers. The ordinance requires all of the city's 950 convenience stores to install "high resolution cameras, silent alarms and drop-down safes" by May 2010. It also requires store owners to register with the city and sign an affidavit allowing police to enforce no trespassing rules.

Dallas Police Office Keith Allen said the biggest problem C-stores face are loiterers and panhandlers, and allowing police to act as the enforcer in these cases protects employees. Prior to this ordinance, a C-store employee had to call police and then physically point out a trespasser to police before he could be forced to leave. Unfortunately, Allen said, that left employees vulnerable.

"Everyone has a horror story about someone approaching them and asking for money or something," Allen said. "They harass customers and put employees in a bad spot. But when we assembled our work group and our committee, convenience stores said mandating having more employees on hand wasn't something a small business could afford."

Joe Williams, vice president regulatory and member services for the Texas Retailers Association, said Dallas' rules are similar to an ordinance Houston develop in 2007 that established minimum standards for the number of video surveillance cameras and the type of lighting to be used in C-stores, and requires stores to clear clutter from windows to increase visibility and minimize the amount of cash on hand.

Dallas' ordinance was developed by a task force of police, neighborhood leaders and convenience store representatives from both local and national chains.

"I know this is going to take some work and it is going to be expensive," Williams said. "And so from a C-store standpoint, it is positive they have both independent and multi-store operators as part of their task force and everyone sat at the table as these rules were being discussed. The capital investment is worth it to protect the employees and the customers."

According to the Dallas Morning News, Dallas police responded to 6,300 calls at C-stores between 2004 and 2007 — 950 of those were classified as violent crimes.