DOVER, Del. — A Kent County judge has refused to declare a mistrial in the prosecution of a former death row inmate being retried in a drug-related killing.

Isaiah McCoy’s lawyers asked for a mistrial following a courthouse confrontation this week between McCoy and a prison guard, whom McCoy allegedly threatened. McCoy himself did not want a mistrial and at one point told the judge he wanted to fire his attorneys and represent himself.

Prosecutors did not oppose the request for a mistrial and told the judge Thursday that they believe he was required to recuse himself based on what he was told by the guard and McCoy.

The judge disagreed, however, and let the bench trial resume.

McCoy, who waived a jury trial, is charged with killing 30-year-old James Mumford in 2010.