The human rights organization, which opposes the death penalty, said 80 percent of the 845 people executed since the United States resumed the practice in 1977 were put to death for killing whites.
A disproportionate number of those executed were black and many were convicted by juries containing no blacks, the group said in a report.
Amnesty International contended the findings, compiled from government statistics and its own tracking, show the death penalty is applied unfairly. It released the report now because 290 blacks have been put to death as of April 10 and at least 10 more black inmates were scheduled to be executed by the end of July, which would bring the total to 300.
Kent Scheidegger, legal director of the pro-death penalty Criminal Justice Legal Foundation, blamed racial differences on fewer prosecutors in heavily minority areas willing to seek the death penalty.
"Prosecutors in more conservative counties use the death penalty more often," Scheidegger said. "That produces an effect that it's used more often in white victim cases. But that's not discrimination, that is politics."
Blacks comprise 12 percent of the U.S. population, but 41 percent of those on death row and 35 percent of those executed between 1977 and 2001 were black, according to the Justice Department's Bureau of Justice Statistics.
Amnesty's research found one in five blacks executed was convicted by a jury without any blacks. "A jury of one's peers is supposed to be broadly representative of one's peers," said William F. Schulz, the group's executive director.
The Supreme Court ruled in February that Texas death row inmate Thomas Miller-El, who is black, deserved a new chance to press his claim that prosecutors stacked his jury with whites and death penalty supporters.
A Justice Department report in 2000 found that between 1995 and 2000, almost three-fourths of the 183 federal defendants facing the death penalty were minorities, and 43 percent of the defendants came from just nine of the 94 U.S. attorney districts: Puerto Rico; the Eastern District of Virginia; Maryland; the Eastern and Southern districts of New York; Western District of Missouri; New Mexico; Western District of Tennessee; and Northern District of Texas.
Attorney General John Ashcroft attributed the figures to differences in state laws, prosecution decisions and geography. "There is no evidence of racial bias in the administration of the federal death penalty," Ashcroft told federal lawmakers in June.
Some recent studies have concluded otherwise.
An Illinois study found juries were three times more likely to sentence a person to death if the victim was white rather than black. Gov. George Ryan cited those findings in January when he commuted 167 death sentences.
A Pennsylvania Supreme Court-appointed commission reported last month that black defendants are more likely to be sentenced to death and recommended a moratorium on executions while the issue was studied.
By Jonathan D. Salant