The answer to "Why was Walter Scott shot in the back while running away?" is simple: he was shot because a police officer chose to shoot him. (For more on the circumstances of Scott's killing, see German Lopez's excellent overview of the case.)

But the answer to "Why was Walter Scott running away?" is harder. And in an extraordinary story published today, the New York Times's Frances Robles and Shaila Dewan offer a surprising explanation: child support.

Scott has been repeatedly sent to jail for failure to pay child support. By the time of his death, he owed $18,000, and there was a warrant out for his arrest. He had ended up in a vicious cycle: he couldn't pay child support because he couldn't hold a job, and he couldn't hold a job because he kept getting thrown in jail for failure to pay child support.

According to an interview the Times conducted with Scott's brother, Rodney, "The warrant, the threat of another stay behind bars and the potential loss of yet another job caused him to run."

But the Times's story goes far beyond Scott to show the way well-meaning laws have trapped poor men in a vicious spiral of debt and imprisonment.

"In 2009, a survey in South Carolina found that one in eight inmates had been jailed for failure to pay child support," the Times reports. A 2007 Urban Institute study looked at child support debt in nine large states and found that 70 percent of it was owed by people with either no reported income or reported income of $10,000 a year or less.

But the crazier number is this one: among that group making $10,000 or less, they were expected to pay, on average, 83 percent of their annual income in child support.

There are caveats to all of this, of course. Some people who appear to be making less than $10,000 are actually hiding income. But it's a rare case where someone who looks to be making $5,000 annually is actually rolling in it.

This system exists for a reason, of course: there really is a problem with deadbeat dads who don't pay child support. But a system that makes sense for collecting on debts from people who have money doesn't make much sense when it's collecting on debts from people who don't have money.

"While every parent has a responsibility to support their kids to the best of their ability, the tools developed in the 1990s are designed for people who have money," Vicki Turetsky, the commissioner of the federal Office of Child Support Enforcement, told the Times. "Jail is appropriate for someone who is actively hiding assets, not appropriate for someone who couldn’t pay the order in the first place."

A 2011 Supreme Court ruling has already held that no one should be jailed unless they actually have the ability to pay their debts. But that ruling isn't always followed by the courts. And the definition of what it means to be able to pay your debts can vary. The Times notes that in some jurisdictions, the judgment of how much someone needs to pay isn't based on their actual income but on their hypothetical income "if they had a full-time, minimum wage or median wage job."

The responsibility for Walter Scott's death lies with the police officer who pulled the trigger, not our child support system. But Scott's sad history in the months before his shooting death is a stark example of how laws that work one way at the top, or even middle, of the income scale can work very differently, and much more destructively, at the bottom.

For more on this, read the whole Times article. It's a powerful piece of reporting.

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