The lawyers questioned prospective jurors in groups of 14. “I happen to represent a young man who is African-American,” Mr. McClatchey said. “If you were in deliberations and someone said something prejudiced, would you speak up?” Thirteen people, both black and white, said they would. “No,” said a white woman. “Their opinion is theirs.” Neither side challenged her, and she was seated.

The prosecutor, Treneisha Hill, who is black, asked many more questions. “Tell me one thing about you that would make you a good juror for this case and one thing that wouldn’t,” she said. The jurors responded to the second part of her query with common themes.

They were worried about crime. They did not want to miss work. A white woman said she might not be able to be fair because her husband had recently been robbed at gunpoint. “He was an African-American man,” the juror said, glancing at Mr. Dudley. “I look at him and think, ‘Were you the one who held a gun to my husband’s head?’”

Mr. McClatchey used a peremptory strike to dismiss her. “It’s like cutting the mold off the cheese,” he later explained.

In the end, he used nine peremptory challenges, three of them to strike blacks. The prosecutors used four, only one to strike a black potential juror, a young man with dreadlocks, much like the defendant’s.

That did not surprise J. Antonio Florence, a defense lawyer here not involved in the case. “Young black men,” he said, “have absolutely no chance of getting on a jury.”

The final panel — 12 plus an alternate — included six black members, all women. Mr. McClatchey said those demographics could work against him, as the black jurors might identify with the prosecutor rather than with his client. “They’ve gotten smart,” he said of recent hiring practices by the district attorney’s office.