A Department of Justice watchdog officially condemned the U.S. Drug Enforcement Administration this month, following a report that the agency had recruited a Transportation Security Administration security screener to search bags for cash that the DEA could confiscate.

The very existence of such a partnership highlights much broader concerns about the controversial legal practice known as civil asset forfeiture, which critics say contorts law enforcement priorities and props up a system of policing for profit.

In a summary of its investigation, the DOJ's Office of the Inspector General concluded that the agreement "violated DEA policy" on a number of levels. While the OIG determined that the TSA informant never provided any actionable information to the DEA, it concluded that the plans to pay the agent out of the cash he or she helped seize "could have violated individuals’ protection against unreasonable searches and seizures if it led to a subsequent DEA enforcement action."

In effect, the OIG was questioning the propriety of an arrangement in which a TSA agent would use his or her power to tip off the DEA to the presence of cash in travelers' luggage, and then receive compensation based on how profitable that information was to the agency.

Robert Everett Johnson, an attorney for the libertarian public interest law firm Institute for Justice, says the same criticism could be made about the entire practice of civil asset forfeiture, which allows law enforcement officials to seize a person's property -- including cash, cars, jewelry and houses -- without obtaining a conviction or even charging the owner with a crime.

"This really is what we see every day around the country -- when law enforcement takes property using civil forfeiture, law enforcement is able to keep that property and use it to fund their budgets and in many cases even to pay the salaries of people who are overseeing the forfeitures," said Johnson.

"That creates an obvious financial incentive to take property from people who haven't done anything or haven't been proven to have done anything wrong. It creates an incentive for all kinds of abuse," he added.

Civil forfeiture has become a critical source of revenue for law enforcement over the past decade, with state and federal agencies now taking in hundreds of millions of dollars in property, and likely more, each year. Cash has meanwhile emerged as a favorite target for police, even if it's just hundreds or thousands of dollars.

Transportation hubs are a particular point of focus for the DEA. A 2015 OIG report found that from 2009 to 2013, the DEA seized $163 million in 4,138 individual cash seizures, many of which were contested and later overturned. The agency has also come under fire in recent cases that involved agents seizing cash from airline and train passengers, and in some cases, allegedly shaking them down.

In the Justice Department report this month, the OIG also called out the DEA for paying an Amtrak informant nearly $1 million over two decades to provide them with passenger information that was already available to the agency.

Law enforcement officials regularly tout civil asset forfeiture as an important tool for fighting the drug trade, because it allows them to go after property directly, without any evidence of criminal behavior on the part of its owner. Drug traffickers, they say, are smart enough not to carry cash and contraband at the same time.

Of course, it's not actually illegal to put a few thousands dollars into a checked bag -- but in the mind of some drug warriors, any individual carrying a large amount of cash must have obtained it illegally, even if the authorities can't prove it.

Officers will often seize cash based solely upon this presumption, and then work to build a case for permanent forfeiture. Under federal guidelines and many state laws, however, law enforcement can win cases based on very weak evidence, which often has the effect of leaving property owners with the burden of proving that their property isn't related to criminal activity.

The DEA has also come under fire in recent cases that involved agents seizing cash from airline and train passengers, and in some cases, allegedly shaking them down.

Critics say this process inverts the American legal principle that suspects are innocent until proven guilty, and takes a particularly harsh toll on people who are already disadvantaged and may not have the resources to fight a prolonged legal battle.

Beyond the legal objections, opponents of civil asset forfeiture maintain that such a cash-focused approach to policing can fundamentally change the purpose of law enforcement, leading officers to prioritize activities that bring in more money, rather than those that focus on public safety.

Johnson said the TSA case highlights these concerns, and demonstrates that the DEA is willing to go to great lengths to expand its ability to make profitable seizures.

"That's really what the OIG is saying: The TSA agents should be focused on doing their job the way the TSA wants them to be doing their job, not what they're getting paid to do by the DEA," Johnson said. "It just warps the TSA agents' priorities."

And while the Justice Department's investigation reveals exactly the sort of shady behavior that a system of policing for profit rewards, critics like Johnson say it's time for federal authorities to take a harder look at the tool that enables this system to thrive in the first place.

"If this is so problematic that it merits condemnation by the OIG, then I hope the OIG will be putting out their next report on why civil forfeiture should be abolished as well," Johnson said.

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