The undercover policeman stands in the shadow of the border fence, watching his countrymen go north.
Wraiths in the fog, the migrants surge up the concrete levee of the Tijuana River. Their furtive progress is lit by bonfires, spotlights, a swooping U.S. Border Patrol helicopter. They scramble up the 10-foot corrugated metal fence and pause--suspended between Mexico and the United States, between a desperate past and an uncertain future.
Comandante Joel Alcaraz scans the crowds with the gaze of a hunter and of a shepherd. His eyes search among the nightly advance of potential victims for robbers, rapists, swindlers. And crooked cops.
"Every one of these migrants is a story," says Alcaraz, a serene former homicide detective in a leather jacket, his wire-rimmed glasses glinting and his breath steaming in the cold. "They save all their money. They sell everything--the chickens, the cow, the little house, so they can bring their whole family. And they get robbed."
Alcaraz belongs to Grupo Beta (Beta Group), an elite Mexican police unit with the most dangerous beat in the Tijuana-San Diego metropolis: the border.
Founded in the reform-minded atmosphere fostered by President Carlos Salinas de Gortari, Grupo Beta is a relatively new, multi-agency border force made up of federal, state and city officers who are charged specifically with protecting migrants from crime.
In 16 months, this extraordinary law enforcement experiment has improved U.S.-Mexican relations, reduced violence and remained generally free of misconduct and corruption, according to San Diego police, the Border Patrol, U.S. conservatives, immigrant rights watchdogs in Tijuana and San Diego, and the border-crossers themselves.
U.S. authorities say Grupo Beta has contributed to encouraging statistics: Homicides in the border area dropped from 10 in 1990 to none in 1991. The amount of money spent replacing windshields of Border Patrol vehicles has shrunk in half because the Mexican officers break up rowdy rock-throwing groups. Assaults on Border Patrol agents have declined 39%. Drug seizures are up.
Gustavo de la Vina, chief Border Patrol agent in San Diego, calls Grupo Beta "a dedicated bunch of guys and gals. They have made it a lot safer for our people and illegal aliens and everyone concerned."
"It's better now. Before it was all thugs and bums around here," said Chuey, a chubby, sleepy-faced teen-ager, who charges $85 to guide immigrants to a San Ysidro fast-food joint where rides to Los Angeles await.
Despite the praise, the 36 officers of Grupo Beta find themselves on treacherous and lonely turf. At a crucial time in Mexico-U.S. relations, they work under a political microscope.
They have clashed with other Mexican police by cracking down on renegade officers who once roamed the area extorting and abusing migrants.
And they navigate a narrow course between their government's policy, which opposes interference with the emigration of Mexican citizens, and U.S. authorities asking for more help against drug runners and smugglers of illegal immigrants.
While crossing the border is not considered a crime in Mexico, smuggling immigrants is. But the law is enforced selectively: Grupo Beta concentrates on large-scale operations while it monitors the more small-time smugglers.
"Our fundamental mission is protection of the migrant," said Javier Valenzuela Malagon, the psychologist and former university professor who heads Grupo Beta.
Grupo Beta's mission recalls the swashbuckling undercover team created in 1976 by the San Diego Police Department to fight rampant violence against immigrants.
The Border Alien Robbery Force, as it was known, engaged in numerous shootouts with bandits and a few shootouts with Mexican police as well. Its harrowing adventures were chronicled in Joseph Wambaugh's book "Lines and Shadows." The unit was eventually disbanded after officials became concerned about the controversial shootings and the danger the officers faced.
A uniformed San Diego team called the Border Crime Intervention Unit operates today. But instead of shooting at each other, BCIU and Grupo Beta officers shoot together--at a San Ysidro firing range. They also maintain constant radio contact and share information, unprecedented steps that show how far the relationship has come.
On a recent Friday night, the BCIU men, known as "Los SWAT" in Tijuana, crossed the border at the port of entry to visit the cramped Grupo Beta offices. Officers made jokes and discussed a robber with a shotgun who was operating just north of the fence in San Ysidro. The conversation took place in Spanish.
"It is an excellent relationship," said Lt. Adolfo Gonzalez of BCIU, which has donated bulletproof vests and radios to its Mexican counterpart.
Today, both units take pains to respect international boundaries when on patrol and refrain from crossing the border except at authorized entry points, Gonzalez said.
Grupo Beta officers generally work in plainclothes teams of three. They melt into crowds on foot, gathering information from vendors and smugglers , shadowing and questioning suspected thieves, drinkers and other potential lawbreakers.
They are carefully screened, trained and monitored. As an incentive against corruption, they make about $1,000 a month--about three times as much as municipal police and about double the average state police salary.
When allegations did surface that several officers tried to shake down migrants or suspects, those officers were dismissed, Valenzuela said.
"Grupo Beta is demonstrating how, with political will, there can be a police force free of corruption that does its job well," said Tijuana human rights advocate Victor Clark Alfaro.
Officers say the system is unlike anything they have encountered in Mexican law enforcement, emphasizing group discussions and sensitivity to the public. Unlike counterpart U.S. units, which have been involved in periodic controversial shootings over the years, officers in Grupo Beta have yet to shoot anyone.
The commander of this quixotic venture is Valenzuela, a slight, cerebral psychologist with a background in 1960s-era student activism. The 40-year-old Valenzuela spent 10 years as a university professor in Mexico City and eight years working with indigenous groups in rural provinces.
The despair and dignity he saw deepened his sympathy for Mexico's impoverished migrant population. He got a chance to test his ideals against the reality of police work when he was chosen to head the new multi-agency force.
"It had to be distinct from traditional police," said Valenzuela. "It had to be a professional, honest project with a mystique of protection and service. In the moment that we gave in to temptation, we would become another group like all of those who prey on people at the border."