The weight of the graduate cap pulls a student down a mountain.

On Adriene McNally’s 49th birthday in January, she heard a knock on the door of her modest townhouse in northeast Philadelphia.

She was served.

“They actually paid someone to come and serve me papers on a Saturday afternoon,” she said.

The papers came from a government lawsuit that represents more than just an unwelcome birthday present – it’s an example of a program the federal government has implemented in 19 cities across the country, including Brooklyn, Detroit, Miami and Philadelphia: Sue to recover unpaid student loans, like those McNally owes.

Everyday, 3000 people by default on their federal student loans – and that lack of payments amounts to an unpaid bill of $ 137 billion for the federal government. For decades, the government has tried to get borrowers to pay by hiring debt collection agencies to call and send letters. But now the government is trying this new prosecution strategy.

McNally filed for bankruptcy in 2006 and liquidated all of his creditors except student loans, which are almost impossible to get rid of in bankruptcy. As she and many others have discovered, escaping federal student loan debt is not easy.

“Your whole body heats up in frustration,” McNally says. “I’m so frustrated with all of this. They’ve been mailing me and threatening me on the phone for so many years.”

In the past two years, more than 3,300 student loan borrowers have been sued for default, according to the Justice Department. In almost every one of these lawsuits, the borrower loses and the government wins.

What does the government gain? A lien on the borrower’s assets, which means that the debt is now attached to their most valuable assets, such as a house.

Jennifer Schultz, a lawyer with Community Legal Services in Philadelphia, says privilege traps a person, like handcuffs.

“I describe a lien as a sort of marker on the house,” says Schultz. “Anytime a person tries to make a transaction involving their home – a new mortgage, a refinance, or if they try to sell it – they are expected to write off any debt related to that house.”

The government has long been able to garnish wages, take tax returns, and steal social security and disability benefits. But targeting real estate is one way to exert even more pressure to charge alumni.

“It’s to try and wake the avoidant from his sleep,” says Drew Salaman, a debt collection attorney in Philadelphia.

Salaman doesn’t work with student loans, but he is well versed in debt avoidance. He says some of the borrowers are playing ‘catch me if you can’. These lawsuits ensure that people take responsibility for their debts.

“After all,” he said, “if we don’t have a system in place to collect debts, how can credit be extended?

The end result of these lawsuits – liens – can be seriously threatening for borrowers. For many, it’s a question of housing preservation, says Joanna Darcus, an attorney for the student loans team at the National Consumer Law Center.

“For people who already live on the fringes of finance, the fear of losing that home may be acceptable,” says Darcus.

Once a lien is in place, the government can force the sale of a former student’s home. It’s “extremely rare,” officials say, but it does happen sometimes.

The federal lawsuit program is expected to continue to grow, and with more than 8 million people currently in arrears on their federal student loans, it doesn’t look like private companies will be short of work anytime soon.

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