The U.S. Drug Enforcement Administration has paid some airline employees hundreds of thousands of dollars to provide flight itineraries of suspected drug traffickers, leading to the seizure of millions of dollars and prompting concerns about the constitutionality of the cash grabs.

In Chicago, the once-secret program led the DEA to seize $5,000 from a United Airlines passenger’s luggage during a layover at O’Hare Airport last year, according to a lawsuit the man filed.

Breland Barcel Lee, a convicted drug dealer, turned up on the government’s radar when a confidential source flagged his one-way ticket as suspicious and alerted a DEA task force officer at O’Hare, court records show. Officers then searched his Olympia roller bag and found the cash. Lee says he was carrying the cash because he was planning to move to California.

“It’s Big Brother,” says Lee’s attorney, Brendan Shiller. “Innocent people are being swept up, and their property is being taken.”

According to a lawsuit Lee filed against United Airlines and members of a DEA task force, the agency seized $5.5 million in suspected drug money from 118 travelers at Chicago airports in a single year, 2015. The money is split among the DEA and the police agencies that work on its interdiction task force.

The DEA, responding to Chicago Sun-Times questions, acknowledges it “routinely receives information from a wide variety of sources, which includes transportation service employees.

“Because drug traffickers routinely use parcel services, airlines, trains, buses and other means to move their drugs and drug currency throughout the United States, DEA routinely works with personnel from these agencies to interdict these substances.”

Last year, the Justice Department’s inspector general’s office issued a report raising concerns about the DEA using confidential sources in the airline industry. It looked at the files of 19 DEA “limited-use” sources in the industry.

The federal drug-fighting agency paid those 19 people a total of $1.6 million for information they provided in 381 cases between 2011 and 2015, according to the Justice Department watchdog — an average of more than $84,000 apiece, with one airline source getting a whopping $617,000 over that period. The DEA’s Chicago office was among six of the agency’s offices that were audited.

The information that the paid sources gave the DEA resulted in reported cash seizures of more than $14 million from passengers, according to the inspector general, who questioned whether those lucrative relationships might violate travelers’ constitutional rights.

Limited-use sources are supposed to act without direction from the DEA. But the inspector general found that, rather than getting unsolicited tips from them about individual travelers, some DEA agents ask their sources to provide entire passenger manifests on an almost-daily basis. Some sources were being cited 20 times a day.

That “calls into question whether a source is truly providing information independently or is acting as DEA’s agent, the latter of which could have implications relating to compliance with the Fourth Amendment’s protections against unreasonable searches and seizures,” the inspector general wrote.

Lee sued United Airlines and members of the DEA Interdiction Group 24, which seized the cash on April 13, 2016. He says his privacy rights were violated when an unknown United Airlines employee handed over personal information about Lee to the DEA, even though he wasn’t a suspected terrorist or threat to national security.

Lee, 31, previously had been convicted of drug and weapon charges — with one drug arrest in North Carolina just two months before his money was seized at O’Hare.

The DEA was alerted to him because he bought a one-way ticket from Raleigh-Durham International Airport in North Carolina to Los Angeles the day before his flight.

DEA task force officers looked at Lee’s social media accounts and found pictures of him posing with large amounts of cash “consistent with narcotic proceeds,” according to the application for a federal warrant to search his bag. They also did a background check that turned up his convictions.

Officers delayed Lee to question him about the contents of his bag. They said he initially denied having any cash, then opened his bag and showed them a leopard-patterned pouch that he says contained his money. The officers said Lee told him he planned to use the money to move to California and that he denied having more than $5,000 in the bag.

The officers said he wouldn’t voluntarily let them search the bag, so they told him they were taking it to have a drug dog sniff it, gave him a receipt and seized it.

A narcotics dog alerted to the presence of drugs in his black roller bag, a task force officer said. They obtained a search warrant and found $5,000 inside.

Though agents seized his money, Lee wasn’t charged with any crime. He was allowed to continue on his trip — which is common practice in cases in which the government seizes suspected drug proceeds.

Lee didn’t challenge the seizure through the government’s civil forfeiture process. Instead, he filed suit last July against United Airlines and DEA task force members.

“They should have more evidence to stop somebody,” Lee says. “They are hurting more innocent people than people who are doing illegal things.”

Lee says he’s a carpenter and part owner of a tobacco shop in North Carolina. He says he was planning to leave the shop to a partner and move to California to “start a new life.”

He says he still wants to move to California, but the seizure set his plans back.

The DEA’s application for the search warrant for Lee’s luggage says the agency received Lee’s travel itinerary from a paid, confidential source who previously had provided reliable information. The application doesn’t say whether the source worked for United Airlines, but Lee’s attorney says there’s strong evidence pointing to that, including the inspector general’s report.

Lee won a partial victory in December, when the village of Glen Ellyn settled on behalf of a police officer who worked on the DEA task force and participated in the search of Lee’s luggage. Lee got $6,000 in the settlement — reimbursement for the $5,000 in seized cash, plus $1,000 to pay his legal fees.

Lee didn’t sue the DEA itself.

United Airlines is the only remaining defendant in the case. On Monday, a judge threw out the federal claims against United but ruled the case could continue on claims based on state law, including infliction of emotional stress and false imprisonment.

In response to questions from the Sun-Times, United Airlines issued a one-line, written statement saying, “United complies with written requests from law enforcement for information and believes this case has no merit.”

In court papers, the airline’s lawyers say the allegations that “United was somehow acting as an agent of the DEA” are baseless.

The airline, which recently was the subject of a huge public backlash with the release of a video showing a passenger dragged off a United flight at O’Hare, didn’t respond to questions about whether its employees are secretly providing information to the DEA.

The inspector general’s report didn’t cite any airlines by name.

According to that report, the DEA needs better oversight of payments to its sources working in the transportation industry, including airlines — and of how the agency uses those sources.

The inspector general was troubled that DEA agents didn’t always disclose the use of airline sources in their investigative reports.

Shiller says that lack of transparency is at the heart of Lee’s case. “We’ve been kept in the dark,” he says.

Attorneys for passengers have been told almost nothing about how DEA agents target their clients’ luggage, Shiller says.

He says he reviewed other DEA applications for warrants to search luggage at O’Hare. In one case, a DEA task force officer disclosed that he conducted routine reviews of flight manifests of planes leaving O’Hare. But the officer didn’t say how he got that information, including whether he relied on a confidential source.

The warrant for Lee’s luggage mentioned the use of a confidential source in small print in a footnote.

Testifying last month before the House Judiciary Committee, Acting DEA Administrator Chuck Rosenberg was asked about the inspector general’s concerns about his agency using airline employees as informants. Rosenberg said they’re being more closely monitored now.

“So confidential sources, confidential informants are very important to our work,” Rosenberg testified. “But we have to make sure we’re careful.

“We’re now doing 90-day reviews of every single one of our confidential sources. We’ve put in place an awards review board so we can make sure that confidential sources are paid and treated the same way.”

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