Debtors' prisons, in which people are thrown in jail for not being able to pay their debts, have been ruled an unconstitutional violation of the Fourteenth Amendment. So how is it that they are making a comeback in the United States?

Across the country, cities and counties are throwing poor people in jail for failing to pay legal debts they could never afford to pay. Failure to pay incurs late fees and more fines which can land the defendant in jail, only adding to the burden of fees they must pay.

A recent New York Times article detailed the case of an Alabama woman whose $179 speeding ticket ballooned into $3,170 and 40 days in jail when she failed to appear in court. She has little hope of ever getting out from under the debt.

The end result of such practices is that poor people often end up paying more in fines and spending more time in jail than those more affluent who are able to pay up front. Although courts attempt to collect legal financial obligations from poor and rich defendants alike, those who can afford to pay are able to move on with their lives. Those unable to pay end up incarcerated or under continued court supervision and paying much more in fines and fees.

It's a problem in Montana, too.

Last week the ACLU of Montana filed an amicus brief in a case in which the defendant was assessed fees he cannot afford. He was given a public defender because the court determined he could not afford to pay for his own legal representation, yet the court imposed attorney's fees and other court costs upon him before even assessing the total cost of those fees or the defendant's ability to pay in keeping with state statutes. This practice infringes on his right to due process.

The ACLU details issued a report in 2010 detailing the societal costs of imposing such fees on the indigent.

In for a Penny: The Rise of America's New Debtors' Prisons, examines how these defendants face the prospect of having to rebuild their lives after prison under the cloud of unmanageable legal debts, living under constant threat of being sent back to jail or prison, solely because they cannot pay.

Being poor is not a crime.