“Every job he has had, he has gotten fired from because he went to jail because he was locked up for child support,” said Mr. Scott, whose brother was working as a forklift operator when he died. “He got to the point where he felt like it defeated the purpose.”

Walter Scott’s death has focused attention not just on police violence, but also on the use of jail to pressure parents to pay child support, a policy employed by many states today. Though the threat of jail is considered an effective incentive for people who are able but unwilling to pay, many critics assert that punitive policies are trapping poor men in a cycle of debt, unemployment and imprisonment.

The problem begins with child support orders that, at the outset, can exceed parents’ ability to pay. When parents fall short, the authorities escalate collection efforts, withholding up to 65 percent of a paycheck, seizing bank deposits and tax refunds, suspending driver’s licenses and professional licenses, and then imposing jail time.

“Parents who are truly destitute go to jail over and over again for child support debt simply because they’re poor,” said Sarah Geraghty, a lawyer with the Southern Center for Human Rights, which filed a class-action lawsuit in Georgia on behalf of parents incarcerated without legal representation for failure to pay. “We see many cases in which the person is released, they’re given three months to pay a large amount of money, and then if they can’t do that they’re tossed right back in the county jail.”

There is no national count of how many parents are incarcerated for failure to pay child support, and enforcement tactics vary from state to state, as do policies such as whether parents facing jail are given court-appointed lawyers. But in 2009, a survey in South Carolina found that one in eight inmates had been jailed for failure to pay child support. In Georgia, 3,500 parents were jailed in 2010. The Record of Hackensack, N.J., reported last year that 1,800 parents had been jailed or given ankle monitors in two New Jersey counties in 2013. (The majority of noncustodial parents nationwide are men.)