Such challenges are rare, and most lawyers are capable of offering reasons unrelated to race. Many legal experts say the Batson ruling has turned out to be toothless and symbolic. But Monday’s case, Foster v. Chatman, No. 14-8349, appeared poised to be an exception.

“Isn’t this as clear a Batson violation as this court is likely to see?” Justice Elena Kagan asked.

The case certainly had unusually vivid evidence. In notes that did not surface until decades after the trial, the result of a public records request, prosecutors had marked the names of black prospective jurors with a B and highlighted those names in green.

They circled the word “black” where potential jurors had noted their race on questionnaires. They ranked the black prospective jurors in case “it comes down to having to pick one of the black jurors,” as the prosecution’s investigator put it in a draft affidavit at the time.

In the end, prosecutors struck all four black potential jurors.

When challenged, Stephen Lanier, the lead prosecutor, denied that race had been a factor and offered other reasons for the strikes. The black prospective jurors were confused, incoherent, hostile, disrespectful or nervous, he said, and three did not make enough eye contact.

“All I have to do is have a race-neutral reason,” Mr. Lanier said at the time, “and all of these reasons that I have given the court are racially neutral.” The judge rejected the defense’s objection.