In 2006, Laurie Lynn Bartlett killed her boyfriend.

She said he was drunk and tried to sexually assault her. She put a knife in him and got 10 years.

A year later, Ernestine Broxsie killed her ex-boyfriend.

She said he "snapped" and began choking her, so she put a bullet in him. She went free.

Two similar cases with one big difference — Bartlett's victim was white, Broxsie's was black.

The dramatic contrast in outcomes might not have had anything to do with the victims' race. But it reflects a reality about Florida's controversial "stand your ground" law.

A Tampa Bay Times analysis of nearly 200 cases — the first to examine the role of race in "stand your ground" — found that people who killed a black person walked free 73 percent of the time, while those who killed a white person went free 59 percent of the time.

"I don't think judges or prosecutors or whoever works in the field of criminal justice is consciously saying black life is worth less than that of other ethnicities,'' said Kareem Jordan, a criminologist at the University of Central Florida. "But at the end of the day, it could be something that's subconscious going on if you look at how the media depicts black life.''

Questions of race have surrounded Florida's "stand your ground" law since the February shooting death of Trayvon Martin, an unarmed black teenager, by George Zimmerman, a Hispanic neighborhood watch volunteer.

Did the teenager's race have anything to do with the initial decision not to charge Zimmerman?

If Zimmerman had been black, would authorities in Sanford have been so quick to accept his claim of self-defense? Are black defendants less likely to walk free than people of other races in "stand your ground" cases?

The Times analysis found no obvious bias in how black defendants have been treated:

• Whites who invoked the law were charged at the same rate as blacks.

• Whites who went to trial were convicted at the same rate as blacks.

• In mixed-race cases involving fatalities, the outcomes were similar. Four of the five blacks who killed a white went free; five of the six whites who killed a black went free.

• Overall, black defendants went free 66 percent of the time in fatal cases compared to 61 percent for white defendants — a difference explained, in part, by the fact blacks were more likely to kill another black.

"Let's be clear,'' said Alfreda Coward, a black Fort Lauderdale lawyer whose clients are mostly black men. "This law was not designed for the protection of young black males, but it's benefiting them in certain cases.''

The Times analysis does not prove that race caused the disparity between cases with black and white victims. Other factors may be at play.

The analysis, for example, found that black victims were more likely to be carrying a weapon when they were killed. They also were more likely than whites to be committing a crime, such as burglary, at the time.

Experts note that most cases have unique combinations of facts and circumstances that determine whether a person goes free or goes to prison. They caution against drawing conclusions on statistics alone.

And although the Times' analysis likely included most of Florida's fatal "stand your ground" cases, some could be missing. That can make a big difference when there are few cases to examine. For example, the Times found only 26 completed cases in which a black person was killed and only eight fatalities with a Hispanic victim.

The analysis, however, is supported by numerous studies showing disparities in the way whites and blacks are treated by the criminal justice system. Studies have found that all-white juries are more likely to convict black defendants. Someone who murders a white person is more likely to get the death penalty than someone who kills a black person.

Adora Obi Nweze, state president of the NAACP, said she was not surprised that people claiming "stand your ground'' escaped penalty more often when the victim was black. But she sharply questioned whether "stand your ground'' really helps black defendants.

"It's very difficult to isolate the data on one law,'' she said, "when we have so many laws where blacks are disproportionately not released, not given the kind of equity you want in justice."

A rare case

Through news reports, official records and interviews with dozens of prosecutors, public defenders and attorneys, the Times compiled a database of 192 "stand your ground" cases that includes the race of every victim and defendant.

It is the first effort to determine how race affects the outcome for those who invoke the 2005 law.

The review found many cases where people went free after killing a black victim under questionable circumstances.

A Miami man stepped out of his home and shot his ex-wife's boyfriend at least 12 times as he sat in a car. A Jacksonville man standing in his garage shot to death an 18-year-old burglary suspect who was running away from his house. A West Palm Beach teenager shot an unarmed man he thought was demanding drugs.

But the Times found similarly questionable cases in which the victim was white or Hispanic. It also found that mixed-race cases — like that of Martin — are relatively rare.

Of the 88 fatal "stand your ground'' cases that have been decided, only about a fourth involved defendants and victims of different races — including six cases in which a white killed a black, five cases in which a black killed a white and six in which a Hispanic killed a non-Hispanic.

No charges were filed in most of those mixed-race cases.

Often, the self-defense circumstances were evident: A person was being robbed or beaten.

In other cases, the type that critics of "stand your ground'' consider questionable, people killed and went free when they might have avoided a conflict:

• Damian Niemeyer was standing at the bedroom window of his Royal Palm Beach townhouse in December when he saw three men trying to back his motorcycle onto a truck. He called 911, then yelled at the men. When one pointed a gun at the window, Niemeyer, who is white, fatally shot Benjy Young, a black teenager.

• Hygens Labidou, who is black, was driving in Deerfield Beach in 2007 when two white men jumped out of their pickup, pounded on his truck and yelled racial slurs. Labidou, still inside his car, fired his gun, striking both men and killing 28-year-old Edward Borowsky.

• In Pompano Beach in 2010, Patrick Lavoie, a white man, jumped out of his girlfriend's car and accused Cleveland Murdock, a black man, of tailgating. When Lavoie, who had a cigarette lighter in his hand, tried to reach through Murdock's passenger window, Murdock fatally shot him.

Among the few people to be charged in a mixed-race case: Gabriel Mobley, a black Miami Lakes man.

Four years ago, Mobley and some friends started arguing with two white patrons at a Chili's restaurant. When the bar closed, the dispute moved outside and one of the men punched Mobley's friend in the face. Mobley shot and killed both men.

Though Mobley claimed he was acting in self-defense, surveillance video showed one victim had his hands up when he was killed and the other did not seem to be reaching for a weapon. Neither man was armed.

After investigating for months, prosecutors charged Mobley with second-degree murder in what they called a key test of the "stand your ground" law.

Mobley's arrest was "very important because it sends a clear message,'' Miami-Dade State Attorney Katherine Fernandez-Rundle said at the time. "The Legislature passed the 'stand your ground' law, but it is not a free-for-all to execute people.''

A closer look

If the Martin case fueled the perception that Florida's "stand your ground'' law is biased against blacks, the Marissa Alexander case has ignited it.

Alexander, a 31-year-old black Jacksonville woman, told police in 2010 that she had fired a warning shot to get her abusive husband out of the house during an argument in which his two young children were present. No one was hurt, but a judge denied Alexander's motion for immunity from prosecution.

In March, a jury convicted Alexander on three charges of aggravated assault, which carry a mandatory sentence of 20 years in prison. Her lawyer, Kevin Cobbin, complained that "stand your ground" was not being used as legislators intended.

"They did not make (the law) for people running around on the streets shooting people,'' Cobbin said. "They made it for women in their homes trying to defend themselves against abusive, mean men.''

A closer look at Alexander's case reveals a more complex story. After arguing with Rico Gray, her husband, Alexander went to the garage, got a gun from her car and returned to the house. Because of that, the judge who denied immunity concluded she had not been in "genuine fear'' for her life.

And contrary to Alexander's claim of firing a shot into the ceiling, a bullet hole was found in the living room wall at about the height of an adult's head, according to the Duval County prosecutor's office.

The case has become a cause celebre, with the NAACP and a black member of Congress jumping to Alexander's support.

"I have spoken to countless lawyers and they have yet to discover any cases in Florida where an African-American was able to successfully use the 'stand your ground' law defense in a hearing,'' Rep. Corinne Brown, a Jacksonville Democrat, claimed at Alexander's sentencing May 11.

Brown called for a study "into racial disparities in the application of this law.''

But the Times found that blacks and whites have had nearly the same success rate when arguing "stand your ground'' in hearings before a judge.

In four domestic dispute cases similar to Alexander's, judges granted immunity to a black woman and a white woman. Two other white women lost their bids for immunity and got lengthy prison sentences.

State Attorney Angela Corey noted that both judge and jury had rejected Alexander's "stand your ground'' defense.

"None of the physical evidence corroborates her story,'' Corey told reporters. "There was the 911 call … and you can clearly hear the distress in Rico Gray's voice. They had a verbal argument (in which) he said 'I'm outta here,' and she said, 'I've got something for you.' "

Once little known outside of Jacksonville, Corey is now familiar to millions. She is the prosecutor who charged Zimmerman.

A need for tracking

With cases like those of Martin and Alexander grabbing the spotlight, experts say it is essential to systematically track Florida's "stand your ground'' law.

"Given this extension in effect of the power to kill, that's an issue that should be monitored very carefully to see who is using it and who is abusing it,'' said Alfred Blumstein, a criminologist at Carnegie Mellon University.

No one knows for sure how often "stand your ground'' is used as a defense or what racial and ethnic groups are most affected by it. That's because no one keeps track of race or ethnicity in those cases.

For example, about 7 percent of the cases identified by the Times had a Hispanic victim or defendant. But the true percentage is probably far higher because police and arrest records generally classify people as "white'' or "black,'' not Hispanic.

Florida and many other states already keep track of so-called "justifiable'' homicides, including the race of defendant and victim. There is no "stand your ground" designation, however. The federal government compiles more detailed race statistics on crime, largely to ensure that the rights of minorities are protected under civil rights and hate crime laws.

"It's to monitor whether there are abuses in particular areas and by particular agencies,'' said George Kirkham, a professor emeritus at Florida State University who also has worked as a police officer.

Nweze, of the NAACP, agreed it would be a good idea to track "stand your ground'' cases but not without also tracking every other type of criminal case.

" 'Stand your ground' is just one law,'' she said, adding that "there's a whole litany of stuff that goes on'' that can have a disproportionate impact on black defendants and black victims.

Jeffrey Rosky, a University of Central Florida criminologist, agreed that there are racial disparities in the administration of justice.

"As for policymakers, this is where they need to have their judgment brought in as to what's too much,'' Rosky said. "Any kind of disparity is too much to a certain degree.''

Times researchers Caryn Baird, Carolyn Edds and Natalie Watson contributed to this report.