To patrol the remote 262-mile stretch of the U.S.-Mexico border south of Tucson, agents monitor surveillance cameras, sensors, and infrared scopes in the desert. They stalk through mountainous wilderness on foot and horseback. They also search for footprints. The agents try to identify if the shoes that formed the prints are sneakers, work boots, or other footwear; the objective is to match them with shoes worn by people caught crossing the border illegally. (The agents regularly sweep the desert floor clean so they can spot fresh tracks.)
The footprints that don’t match up, along with other evidence of crossers they spot but don’t catch, are counted as “gotaways.” Agents compare the number of gotaways to the number of people turned back or detained; the result is a percentage used to gauge the security of the border. As Manuel Padilla Jr., chief patrol agent for the area, puts it, tallying the number of people who slipped through “is not an exact science.”
Still, the calculation has national repercussions. The agency’s success rate is key to Republicans’ support for immigration reform. The bipartisan bill being considered by the Senate conditions a path to citizenship for undocumented workers on the U.S. Border Patrol stopping 90 percent of crossings at the three most porous parts of the border: Laredo and the Rio Grande Valley in Texas, and the area patrolled by Padilla’s agents south of Tucson.
The Tucson region increased from 67 percent secure in 2006 to 87 percent secure in 2011, a sign to lawmakers and reform advocates that the two Texas regions can also improve their lower rates. “When I first saw the 90 percent, that sounded really high to me,” says Christopher Wilson, an associate with the Woodrow Wilson Center’s Mexico Institute, “but the reality is, it is within reach.”
The Border Patrol has made its gains south of Tucson by reinforcing a 2.5-mile-long fence between Nogales, Ariz., and Nogales, Mexico, and increasing surveillance. The number of agents in the region grew from 287 in 1993 to 4,176 last year. Yet secure as it’s become, the Tucson sector is still the busiest part of the border in terms of the total number of people trying to cross; a third of illegal immigrants caught entering the U.S. last year were apprehended there.
The challenges of eliminating the three-percentage-point gap to get to 90 percent are considerable. Extra security in Nogales has forced people east and west of the city over rolling hills, into deep gulches, and up 7,000-foot peaks. Cameras perched on hilltops can’t see into all the valleys. Roads are nonexistent or impossible to construct, limiting access even by all-terrain vehicles or horses and forcing agents to hike in. Building a fence across the entire 262-mile section of the 2,000-mile-long border isn’t realistic. It costs $6 million a mile to put up a fence on flat land where there’s already a road, and much more on rough terrain, says agent Leslie Lawson. Adds Padilla: “If you put a fence in a remote area without constant agent presence, the likelihood of it being broken down is high.”
The Senate bill provides $1.5 billion for improved fencing and $3 billion for agents, surveillance equipment, and drones. Padilla says investing in more technology to watch over the remote desert is the answer. But there could be a downside to having more precise information, says Edward Alden, a senior fellow at the Council on Foreign Relations. Agents could discover that they are further away from the 90 percent benchmark than they thought. “If you think about it quite logically, they don’t know what they don’t know,” Alden says.
Agents in the Tucson area say they eventually can get to 90 percent. But there is the question of diminishing returns: “What is it going to cost us to build a road, then to build a fence and then secure the fence?” asks Lawson. “Is a 15-foot fence on top of a 5,000-foot peak going to make a difference?”