CLAD in a loose-fitting Army camouflage jacket, Gilberto Guerrera emerges from the scrub and shadows of Smuggler's Canyon. The undercover cop has been chatting with Mexican migrants gathering in the gulch. As night falls, they are preparing to make the dash north across the border.
"The big difference in this job," says the 10-year police veteran pausing to regain his breath, "is there's no temptation to take money. Everything is clean. I feel a lot better about myself."
Mr. Guerrera is a member of Grupo Beta - an elite team of Mexican officers. Formed in August 1990 to combat border bandits and violence, the force is more successful than many had hoped.
"Grupo Beta is an exception to the rule among Mexican police," says Victor Clark Alfaro, president of the Bi-National Human Rights Center in Tijuana. "They represent what can be done in our country when there is the political will."
Dr. Jorge Bustamante, president of El Colegio de la Frontera Norte, lauds the 36-member patrol as a "phenomenon. They're proud and honest - that's extraordinary among Mexican police forces."
Grupo Beta was created in response to increasing victimization of Mexican migrants by smugglers and police along the Rio Grande.
Crossing the border is not against Mexican law, but smuggling people over the line is. About half of all northbound "illegals" pass through Tijuana.
Until Grupo Beta, 50 to 75 percent of all travelers were subject to extortion, according to weekly polls by El Colegio de la Frontera Norte. "It was open season for anyone with a badge or a gun," says one official. Now, only 5 to 8 percent of those polled say they are forced to make payoffs.
Composed of federal, state, and local police and backed by top Mexican officials, Grupo Beta reflects the high priority President Carlos Salinas de Gortari has given to United States-Mexico border problems. Indeed, the Mexican government has been sharply critical of alleged human rights abuses by US police forces against migrant workers. But Mexico realized it must clean up its own backyard, too.
"Frontier violence creates a climate of uncertainty and instability in the relations between our countries. Mexican migrants are not criminals, contrary to what some in the US may believe," says Edmundo Salas Garza, director of migratory services, the government agency under which Grupo Beta operates. "Against the backdrop of the free-trade negotiations, we felt this was something we needed to resolve."
US law enforcement officials praise Grupo Beta for eliminating the "zone of impunity" whereby common crooks or drug smugglers would evade capture by jumping back into Mexico when pursued.
"In the past, when the Border Patrol called for help from Mexican authorities ... we got no response," says Steven Kean, spokesman for the US Border Patrol in San Diego. "Grupo Beta has made a difference. The arrest rate is much higher now."
Among the reasons cited for Grupo Beta's success are strong political backing, intensive training, three-man patrols instead of one or two, regular meetings with lawyers and human rights groups, public recognition, and higher pay. Group members earn about $1,000 a month - 30 to 50 percent more than regular police.
But Beta's chief, Javier Valenzuela Malagon, notes the salary incentive is not the main attraction. When the call went out for volunteers to start the force, nobody stepped forward. "Within the normal corruption there was a margin of extra earnings close to or above our salary," says Mr. Valenzuela. And many police believed Beta would be a short-lived project and participants might be subject to reprisals later by fellow officers.
The force started with just four agents and grew slowly. The low-budget operation has second-hand cars and a grimy office at the San Ysidro border crossing.
But the modest beginnings have helped create the close-knit, professional spirit which Valenzuela has utilized in molding his troops.
Many observers attribute Beta's success to Valenzuela's influence. A former peasant organizer, academic, and psychiatrist, Valenzuela has no police training.
"He's smart and thinks like a cop," insists Joel Alcaraz, a homicide detective with 12 years on the Tijuana force before joining Beta.
"Even with my years of experience, I'm learning things from him. Like how to communicate," he says.
Valenzuela admits to being completely involved in the lives of his men. "I know their families, their wives, children, and all their problems," he says. Not all of his men came to Beta with a clean record.
"Some have been involved in corruption in the past and we've talked about that openly. We've discussed the effects of corruption on the social and moral equilibrium of society. If you take money, that's a crime. It doesn't matter if you have a badge or not. You're a criminal," he says.
A year ago, one of the Grupo Beta officers was kidnapped while he was off duty and executed. Controversial shootings - particularly on the US side - are not uncommon on this beat, frequented by thieves, rapists, and drug traffickers.
But in some 7,000 arrests, only once has a Beta officer fired his pistol. And that was in the air to warn a fleeing suspect. He lost his job - the sole agent who has been fired.
"Discipline is absolute. We cannot permit even the appearance of impropriety," says Valenzuela. Rules prohibit firearm use except in life-threatening situation.
There are discussions underway to duplicate Grupo Beta in other border cities experiencing a high crime rate, such as Ciudad Juarez and Matamoros.
Valenzuela's advice: "Keep it simple. Human contact is very important. We talk constantly, reviewing our own errors, looking for ways to improve."