Don Manuel lives where the border fence ends, in the mountains east of Tijuana. He's heard about the murder of the police chief, about the execution of the lawyer who represented the man allegedly behind Tijuana's drug cartel. But Don Manuel is 86 years old and 2000 feet above the city. And here, where horses are for transport and pigs are for eating and cactus fields are for harvesting and candles light the night, he has a more immediate problem: people have bulldozed his neighbor's houses. Now they're selling lots on a triangle of the land that he and Don Gabino Moreno Santana, the president of their land association, say is theirs.

Tonight a district attorney for the state of Baja California has come to hear their story. Everyone gathers around a fire on the dirt floor of the community hall, which took them a decade to build. They talk while Señora Alma barbecues carne asada and heats tortillas on a metal rack. This meal is a thank you to the DA for his efforts. The smoke curls up and out through the space in the brick wall where a window will be. There's still no electric light or windows or floor, so Don Manuel draws a map in the dust with a stick. "The bulldozers from the ejido [government-granted group-owned lands] down the hill just came one day and destroyed our homes," says Isabel Félix. "No warning. They destroyed the furniture, everything. They even smashed the water tank. It was a good thing the people were at work, otherwise they wouldn't even have their clothes and tools."

Licenciado "Pérez" (who asked that his real name not be used) eats his carne asada and tortilla and beans, sips from a bottle of Tecate beer, and listens. A Baja California state district attorney, he has made the hour-long journey, half of it over rocky, unpaved steep gully roads, to find out about this group's claims.

"Alma wrote a complaint against the people," says Isabel. "The [municipal] police came. But they just looked and left. Don Gabino went to private lawyers, gave them money. Nothing happened! Then he asked people where he could go to get justice. And they told him about the licenciado and the Unidad Orgánica Contra Despojos [the (state) unit against real estate land theft]. He didn't expect much. He is so happy that the licenciado actually came up to us, to see. Licenciado Pérez, he is like a god!"

She laughs, but she means it.

Pérez's day started around 9:00 this morning, like most of his mornings at the downtown Tijuana office that he shares with four other attorneys of the Ministerio Público, the state police and district attorney headquarters, near the bullring.

It's difficult to find the cinderblock house, tucked behind the main building. This is where most Tijuana murders and robberies are investigated. Blue vans pull up and disgorge handcuffed felons. Plainclothes state cops stand around in the sun with square black pistols stuffed into their jeans. Some snack on papaya and cottage cheese and honey from Pedro's fruit stand. Appellants approach public writers -- escritorios públicos -- to help them fill out forms. Smooth-suited defense attorneys in jackets and shades bustle up and down the sidewalk, looking out for their clients.

Among the day's clump of people gathered outside the garden of the Unidad Orgánica Contra Despojos, Don Gabino and a worried-looking woman (who identified herself only as Margarita) wait for Pérez with armloads of papers and plans. Like everybody else, they're here to complain of land invasion. In a city where only 25 percent of the population is satisfactorily housed and 80,000 new settlers arrive each month, this is one of the busiest sections of state law enforcement.

Pérez sits in the back office hearing the denuncias, accusations, by traditionally dressed people from the edge of town.

"This is my work. I sit here and listen to landowners come in and denounce squatters," says Pérez. "If our research backs them up, we enforce. We give the squatters on their land 72 hours to move."

It's rarely as simple as that.

"This is nothing like it was," says Pérez, a quick, short man who enjoys people. He says that back in the '80s there were literally tens of thousands of squatters. It was out of hand: People with no money coming north for work, some of the 26 million Mexicans who live in extreme poverty and 40 million who are considered poor (according to Mexican-government figures quoted by Reuters). They may have had jobs in the maquiladoras but nowhere to live.

"The problem with land in Mexico, mostly on the borders, is the great number of immigrants from inside Mexico," says Pérez. "Too many people; not enough housing for rent and so few houses for sale. And the ones that are average $2000 -- too expensive for these immigrants from little towns with no money.

"So these people started to organize in the early '70s. They went up to the empty hills and claimed the land for themselves, saying that the nation should give [land] to its people, because the constitution guarantees that right to Mexicans -- education, good health, and a place to live with dignity.

"Then the state [counteracted by] approving new laws, including this despojo felony law to try to stop the illegal invasion of land. But for the government it was very difficult to try to grab these thousands of people and put them all in jail. Complete families. It became a conflict between the law and a social problem the government had to deal with."

As he talks, Pérez signs court orders and correspondence with a swirling signature. He says the state eventually created a less stringent law. Squatters would still be tossed off the land, but state and federal agencies would offer them government land to buy at rock-bottom prices -- say, $700 to $1000 -- with low or no-interest drip payment.

"If they leave within 72 hours, we don't prosecute," he says. "And the government is working on their case to provide land for them. A big part of Tijuana is growing because of these kinds of settlements."

Pérez points to a distinguished-looking older man in a big hat waiting outside. "That gentleman has been in jail because he took land and profiteered from the migrants. Líderes sociales like him manipulated immigrants into invading land and then, in effect, making them pay protection money."

But times are changing. "Land invasions are down 80 percent since the 1980s, but there will be new waves. The government has got to find new ways to provide land to the people."

The unusual thing about Pérez's office is that, unlike most bureaucracies, he and his colleagues don't just sit and read files. "Paper is cruel," Pérez says, "and sometimes deceptive. I like to look into people's faces, see the land, find out what's going on."

Half an hour later that's exactly what he's doing. He swings off the highway to Rosarito and up a pitted road to a housing development. Building appears to have stopped halfway through construction. Margarita is here, sitting up front with Pérez. She points to certain houses. "Eighty houses," she says. "That's what the teachers' union was supposed to get. But they've taken over 100, including mine. They're living in them!"

Pérez pores over plans until he finds one house that's occupied. He stops, marks the place on the plan, tucks his gun into the back of his trousers, and goes to speak to two people working in the small garden.

"I'm afraid you are going to have to leave," he says. "Seventy-two hours."

"But I'm a federal-education employee," says the man.

"And I'm a state-education employee," says the woman, Dulce. "And it was the state developer of this project who told us, 'Move in!' "

"The best thing," says Pérez, aware of the lives he is turning upside-down, "is not to wait the 72 hours. Come see our office with your papers."

An hour later we are bumping through the northeasternmost colonia of Tijuana, Las Torres. This is Rinconada Dos. The road is like a potholed rollercoaster ride. Rinconada Dos is one of Tijuana's newest settlements. Four years ago it was empty land. Snaking down into the gully, we ease back up the other side while a blue-and-white bus labeled El Dorado comes lurching by. Plywood shacks dot the hillsides, a few houses too. But it's rough and mostly dirt-scrabble.

"You work out how long it would take a patrol car to come here to [a crime scene]," says Pérez. "Can you imagine? It makes it so easy for a criminal to go hide. And you wonder how big-time criminals start? There are no parks here. There are no places for the kids to enjoy themselves. All these things create an impact on the growing child. They hear songs on the radio saying how well paid a drug dealer gets to be. And they see drug-dealers driving new cars. Then they see their father working in a maquiladora and not improving [his income]. The message is clear: Keep going on the right way and end up living like this, or risk a little and live like a king."

Gustavo Hernández, who's been sitting in the back, directs Pérez up a steep, empty hill to a flat space on its shoulder. Don Gabino and Héctor Villalvazo come to meet Pérez, then escort him to the land they believe has been stolen from their property, the Granjas Familiares [Family Farms], "División del Norte."

"División del Norte was Pancho Villa's famous division, right?" Pérez asks Villalvazo. "Right," answers Villalvazo.

What we see is not exactly a war zone, but concrete slabs where small houses once stood dot the slope. Fences have gone up, lots marked out, a few houses constructed. The siege mood is deepened by the sight of the rusty international border fence dividing the hill beyond. Don Gabino points to a small house painted with signs in the distance. "Oficina Ejido Matamoros," says the main sign. "Nueva Dirección."

Pérez says he'll have to research this issue before acting. Gabino asks if we'll come to the "community hall."

The hall stands unfinished beside a school that went up with the help of San Diego's Rotary Club. Inside the hall, coals glow and smoke rises. Gradually you can make out the men and women gathered here to thank Pérez for taking an interest; since the problem started two years ago, this is officialdom's first recognition. They hand out beers and start cooking the carne asada.

Don Manuel wants to talk about his cactus patch, which gives him "50 to 60 cases of nopales every week" to sell. But Pérez wants to talk business.

"Don Manuel, hear me: Have you been living here for 14 or 15 years? You know how things are?"

"Yes."

"Who had the land fenced? Who are the owners of the land they say has been invaded? Is it these [people] here?"

"Yes."

"Were the lands fenced?"

"Yes."

"And then the [other] ejido showed up?"

"Yes."

"And they tore down fences?"

"Yes."

"And they tore down houses?"

"Yes."

"That's what I wanted you to tell me. How long ago was it that they did this?"

"About two years ago."

"How long?"

"Two years ago."

"When can you come and [make a deposition]? Tomorrow?"

"Whenever you want."

"Then tomorrow, the others will bring you [down to Tijuana] so you can make a statement. Let's go."

"He'll make one of the strongest witnesses," Pérez says half an hour later, as we bump back down toward the valley of lights that is Tijuana. "Even if the people from the other ejido have their own maps, it won't help. Because they took the law into their own hands. They destroyed other people's shelter. They should have come to us."

Nearer town, as we wait for a snarl of buses and pickups to untangle, Pérez exhales a satisfied sigh.

"This is what I love doing," he says. "My official lunchtime is 3:00 to 6:00. But I could tell in my office that these people had real problems. And what more interesting lunch could you have?"

It is 7:00 p.m. by the time we arrive back at state-police headquarters. A light shines in the office; Pérez's secretary is there alone. Out in the garden Pérez sees a shadow. A woman stands up and comes into the light. It's Dulce from the government housing project. She's been waiting since 6:00. She begs the licenciado to see her now and tell her if her papers are really not legal.