Capital One pursues customers long after personal bankruptcy should have wiped out their debt.

An ongoing audit has identified 15,500 allegedly erroneous claims. In one case, Capital One sued a woman for $4,266 in credit-card debt after she'd gone bankrupt, then asked a bankruptcy judge to throw out the woman's countersuit that accused the company of flouting bankruptcy law.

The judge refused.

David W. Houston III, chief judge of the U.S. Bankruptcy Court in Aberdeen, MS., said he plans to "demand that Capital One show up in his courtroom to explain its debt-collection practices."

"I want some proof from the company that this was a legitimate error and not a conscious, malevolent effort to go out and collect a debt that's been discharged," Judge Houston said in an interview.