In Los Angeles County, certain murders are more likely to be solved and successfully prosecuted than others.
Killers of whites are more likely to be punished than killers of blacks or Latinos.
Slayings that get publicity are more likely to end in convictions.
And outcomes vary significantly from police agency to police agency and from courthouse to courthouse.
Those findings emerged from a 20-month study of all 9,442 willful homicides reported by public agencies in Los Angeles County from 1990 through 1994. The study tracked those cases through the justice system until mid-1996.
It examined the impact on these cases of race, class and media attention--all elements in the O.J. Simpson murder case. In short, the study sought to determine how the system works for people not named O.J. Simpson.
The method of analysis stops short of establishing cause-and-effect relationships. It does not prove, for example, that a victim's race is what causes his or her murder to go unpunished. But it does show that the likelihood of punishment varies according to the victim's race.
"The system does a lot of things well, but some things quite poorly," said Richard A. Berk, the UCLA sociology and statistics professor who did the statistical analysis for The Times. "The data suggest that the system treats some victims' lives as more important than others. In particular, it appears to devalue the lives of low-income people and minorities.
"It also may be affected by legally irrelevant factors such as media attention," Berk said. Decisions by prosecutors to file capital charges and enter into plea bargains, he said, "appear to be influenced by the scope and content of newspaper coverage."
The study found that several factors that had nothing to do with the severity of the crime were significant indicators of how cases turned out:
* Victim's race. Cases involving white victims were more likely to be solved by police. And suspects, once caught, were more likely to be charged with crimes carrying a potential death penalty.
Conversely, the slayings of blacks and Latinos were less likely to be solved, and prosecutors were less likely to charge the suspects with capital crimes.
* Social class. The killings of people who lacked high school degrees were less likely to end in murder convictions than killings of people who completed high school or college.
* Publicity. Alleged killers who received newspaper coverage were more likely to be treated severely by prosecutors. And killings of white victims were more likely to receive newspaper coverage.
* Police agency. The Los Angeles Police Department, by far the county's biggest, was more likely to make arrests that led to charges than the Los Angeles County Sheriff's Department. But LAPD cases fell apart in court more often.
* Courthouse. Cases filed in the downtown courthouse, where four out of 10 murder cases are processed, were more likely to end in dismissal--and less likely to end in a murder conviction--than cases in suburban courthouses.
In raw numbers, charges were filed about 10% more often when whites were the victims than when blacks or Latinos were. When the statistical analysis took into account information about the victims and the circumstances of the crimes--such as hard-to-solve killings of strangers or easier-to-solve domestic killings--the odds that killings of whites would be solved were 1.4 times greater than the odds that killings of blacks and Latinos would be solved.
The study looked for factors that might explain different outcomes of cases. For example, the study examined similarities and differences in cases where charges were filed. It then determined the degree to which race or class or other key factors were linked to the filing of charges.
Law enforcement officials say they try to be evenhanded in their approach to homicides, but acknowledge that as a practical matter, not every case gets the same attention. Nonetheless, they say, race is not a factor in how hard they try to solve and prosecute cases.
"We don't say, 'Hey, it's a white person, so we're gonna work harder on this,' " said LAPD Deputy Chief John D. White.
Capt. Don Mauro, head of the Sheriff's Department homicide bureau, said of race: "I don't see where . . . that shows up anywhere in the effort" deputies make.
Dist. Atty. Gil Garcetti and his top aides declined to be interviewed for this series unless they could conduct their own study based on The Times data.
But a Garcetti spokeswoman said in a letter: "Race plays no part in our decision-making process. In fact, we attempt to be colorblind when we file cases and make . . . decisions" in potential death penalty cases.
Law enforcement officials suggest that factors other than race account for the higher proportion of murders of blacks and Latinos going unsolved.