The bipartisan Senate framework for comprehensive immigration reform released on Monday puts a controversial, high-tech tool front and center: drones. The unmanned aerial vehicles allow conservatives and liberals alike to look tough on border security, but critics say the drones are a threat to civil liberties -- and the Department of Homeland Security's own inspector general says they're so wasteful that the border police should stop buying them.

Drones have evolved into a massive industry over the past decade of war, generating $1.3 billion in economic impact just in San Diego, home to Predator maker General Atomics, in 2011. Since 2004, drones haven't been deployed just to hot spots like Pakistan and Yemen in the war on al Qaeda. The Department of Homeland Security has now built a small fleet of 10 Predators, at a cost of roughly $20 million apiece, that are mostly deployed along the US-Mexico border.

The immigration framework released by eight senators on Monday promises that the legislation "will increase the number of unmanned aerial vehicles and surveillance equipment." If immigration reform goes ahead as the Senate group wants it to, drones will take on an even more important role in border security -- a development that critics say could turn the border into a virtual military zone and threaten civil liberties.

Javier H. Valdes, co-executive director of the immigrant advocacy group Make the Road New York, expressed concern in a statement about "undue immigration enforcement provisions in the senators' principles, including the notion that legalization for undocumented immigrants should have to wait for additional border security measures that would further militarize the southwest with aerial drones."

In 2011, American Civil Liberties Union staff attorney Catherine Crump warned that expanded drone use without additional safeguards "could easily lead to police fishing expeditions and invasive, all-encompassing surveillance that would seriously erode the privacy that we have always had as Americans."

That fear has become increasingly real as Customs and Border Protection expands its program of loaning drones to federal and local law enforcement agencies -- a development, the ACLU said, that "was carried out with no public knowledge or debate."

CBP did not immediately respond to a request for comment on its use of drones. In the past, the agency has pointed to the 7,500 people and 46,000 pounds of illicit drugs -- mostly marijuana -- it says drones have kept out of U.S. territory 2005. The drones, CBP says, offer a high-tech, constant presence in the sky that can quickly spot migrants illegally crossing the border or smugglers carrying drugs.

But several problems have come along with the CBP's growing fleet. In 2006, a Predator crashed in Nogales, Ariz., narrowly missing a cluster of homes. The National Transportation Safety Board has faulted CBP for the way it ran its drone program. In May 2012, the Department of Homeland Security's own inspector general, which has internal oversight over the program, issued a report faulting CBP for its management practices and for buying more drones without a plan to make use of them.

In their primary function as border-watchers, the inspector general said, drones are a faulty and overly expensive tool. Following up on that report, an article by the Center for Investigative Reporting found that drones were sometimes stopped from taking off by high winds, and were much less productive than existing, manned planes like the P3 Orion.

"I liken it to using a Humvee as a taxicab," said David Olive, a principal at the lobbying firm Catalyst Partners and a one-time chief of staff for former US Rep. Asa Hutchinson (R-Ark.). "You know what, it will work, it will do the job, but there are so many other things that will do the job better and cheaper."

The inspector general called on CBP to freeze its drone purchases. But the agency forged ahead anyways, inking a five-year, $443 million deal with General Atomics. Congress has yet to authorize the money to actually buy the drones. If immigration reform moves ahead as the Senate's gang of eight wants it to, however, that could change -- and we could see more eyes in the sky.

"It's a good idea in terms of the politics of it; everybody likes to hear about more border security before they talk about immigration reform," said Tom Barry, director of the TransBorder Project at the Center for International Policy. But, he added, "Does it work to control the border? No."

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  • "Gang Of Eight"

    A <a href="">bipartisan group of senators</a> have come together to address the issue of immigration reform. The group consists of four members of each party -- Democratic Sens. Chuck Schumer of New York, Dick Durbin of Illinois, Bob Menendez of New Jersey and Michael Bennet of Colorado, plus Republican Sens. Lindsey Graham of South Carolina, Marco Rubio of Florida, John McCain of Arizona and Jeff Flake of Arizona. Their framework was announced Monday.

  • Pathway To Citizenship

    A <a href="">"tough but fair" </a> road to citizenship is the main tenet of the bipartisan immigrant plan. Sen. Marco Rubio (R-Fla.) is the most significant supporter of this idea, giving hope to those who doubt Republicans will support the plan.

  • The New Process

    The new process of obtaining citizenship would be just that -- a process. Probationary citizens would be required to pass an additional background check, learn English, pay taxes and show that they have a history of employment to apply for permanent residence and a green card. Undocumented immigrants will receive green cards after all probationary citizens have been processed, ensuring that documented immigrants are addressed first. Separate processes would be designed for young undocumented immigrants who came to the US as children and agricultural workers.

  • Enforcement, Then Green Cards

    The first goal, before any green cards are handed out, is to "demonstrate our commitment to securing our borders and combating visa overstays," the senators say in their framework.

  • Enhance Border Security And Drones

    Emphasizing enforcement measures, the framework calls for increased boarder control, including more border agents and aerial surveillance and drones. A new system would be added to ensure visa stays are being adhered to, along with a commission of border lawmakers to aid legislation.

  • Increase Employment Verification

    The senators have proposed to create an "effective employment verification system" that would help prevent identity theft while allowing employers to feel secure in hiring documented immigrants.

  • No Benefits For Probationary Immigrants

    Immigrants who are in the probationary category would not be eligible for federal benefits in the senators' framework. This addresses the concern that public benefits, particularly health-related ones, are being spent on undocumented immigrants.

  • An Easier Path For 'The Best And Brightest'

    The framework recognizes that a different sort of process would be needed for "the best and brightest," including highly-skilled workers and those with higher education. This has been previously addressed in the <a href="">STEM Act </a> which was ultimately vetoed by the White House.