(Recasts lead, adds details on prosecutors' actions, reaction from defense lawyers)

By Lawrence Hurley

WASHINGTON, May 23 (Reuters) - The U.S. Supreme Court on Monday effectively overturned a black man's 1987 conviction for murdering a white woman, rebuking Georgia prosecutors for unlawfully excluding black potential jurors in picking an all-white jury that condemned him to death.

The 7-1 ruling handed a major victory to Timothy Foster, who is 48 now and was 18 at the time of the 1986 killing of Queen Madge White, a 79-year-old retired schoolteacher, in Rome, Georgia. Prosecutors, however, still could seek a new trial.

Black convicts make up a disproportionately high percentage of death row inmates in the United States. Opponents of capital punishment assert that the American criminal justice system discriminates against black defendants.

During jury selection, all four black members of the pool of potential jurors were "struck" by prosecutors, meaning they were removed from consideration. Prosecutors gave reasons not related to race for their decisions to exclude them.

Chief Justice John Roberts, who wrote the ruling, said prosecution notes introduced into evidence that shed light on the jury selection "plainly belie the state's claim that it exercised its strikes in a 'color blind' manner. The sheer number of references to race in that file is arresting."

The notes showed that the prosecution marked the names of the black prospective jurors with a "B," highlighted them in green and circled the word "black" next to the race question on juror questionnaires.

The prosecution gave reasons for excluding potential black jurors including that they "did not make enough eye contact" during questioning and were "bewildered," "hostile," "defensive," "nervous" and "impudent."

Roberts said prosecutors "were motivated in substantial part by race" when two of the potential jurors were excluded. Two such strikes based on race "are two more than the Constitution allows," Roberts added.

The Supreme Court ruled in 1986, the same year as this murder, that it is unconstitutional to take race into account when excluding potential jurors.

Prosecutors said Foster broke into the elderly woman's home in the middle of the night, broke White's jaw, sexually assaulted her, beat and strangled her, and stole items from her house. Foster later confessed to killing White, according to court papers.

'RELIANCE ON RACE'

At the time of the trial, Foster's legal arguments regarding jury selection failed. But in 2006 his lawyers obtained access to the prosecution's jury selection notes, which showed that the race of the black potential jurors was highlighted, indicating "an explicit reliance on race," according to Foster's attorneys.

According to court documents filed by Foster's lawyers, the lead prosecutor said of his exclusion of the potential black jurors: "All I have to do is have a race-neutral reason, and all of these reasons that I have given the court are racially neutral."

Foster's lawyer, Stephen Bright of the Southern Center for Human Rights, said the legal challenge would not have succeeded without the notes.

"This discrimination became apparent only because we obtained the prosecution's notes which revealed their intent to discriminate. Usually that does not happen. The practice of discriminating in striking juries continues in courtrooms across the country," Bright said.

The Supreme Court's ruling threw out a Georgia Supreme Court decision rejecting Foster's claim about prosecutorial misconduct in jury selection, meaning a state court will now reverse his conviction.

The sole dissenter in the ruling was the court's only black justice, Clarence Thomas. Thomas said the case should have been sent back to state courts to determine whether Foster's claim could proceed.

The office of Georgia's attorney general had no comment on the decision. (Reporting by Lawrence Hurley; Additional reporting by Jon Herskovitz; Editing by Will Dunham)

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