The Washington PostDemocracy Dies in Darkness

Six cops were charged in Baltimore. But only one-third of accused cops are convicted.

Marilyn Mosby, Baltimore state's attorney, approaches the podium for a news conference  May 1 in Baltimore. (Alex Brandon/AP)

News that six Baltimore police officers would face charges in the case of Freddie Gray, the young black man whose mysterious death has prompted protests around the country and riots in Baltimore, was met with general surprise from a country that's seen officers go without charges in other recent cases.

The data suggests that surprise is warranted, given how many officers were charged. But history suggests Friday's announcement will not resolve the city's tension — not yet, at least.

Between 2005 and 2011, data from Bowling Green University's Philip Stinson shows, at least 3,328 police officers were arrested for violence-related crimes. The majority of them were off-duty when the alleged crimes occurred, and most were male officers. The charges outlined by the Maryland state's attorney, however, involve six on-duty officers, including a lieutenant and a sergeant.

According to Stinson's data, nationally only 69 lieutenants were charged with crimes over the seven-year period he looked at, along with 269 sergeants. The sergeant facing charges in Baltimore is more of an outlier than that, however. Sgt. Alicia White is also a woman, and only 4 percent (134 instances) of criminal charges studied by Stinson involved female officers.

The state's attorney, Marilyn Mosby, announced 28 charges against the six, ranging from false imprisonment and misconduct to assault, involuntary manslaughter and "depraved heart murder" charges. A "depraved heart murder" is one in which someone acts in a way that creates the risk of death for another person, who then dies. The cause of Gray's death isn't clear, but there is speculation that it was caused by what is called a "nickel ride" — when police put a handcuffed suspect in the back of a vehicle without restraints, and then drive wildly to intentionally cause physical harm.

Stinson's research shows that assaults were the most common charge filed against police officers over the 2005 to 2011 period. Also near the top of the list are sexual assaults and murder. There were 104 instances in which the most severe charge against an officer was murder or non-negligent homicide, and another 43 involving negligent manslaughter (the latter being deaths caused by recklessness).

Detailed analysis of Stinson's work conducted by The Post found that, in the 54 cases since 2005 in which officers on duty shot a suspect to death, officers were not convicted in a majority of the resolved cases. "Jurors tend to be sympathetic toward police officers," one officer's attorney told The Post, which makes convictions more difficult. Of all of the 3,200-plus charges brought against officers in the period Stinson studied, only about one-third were eventually convicted of their crimes. That's about half as often as in felony cases in the country's largest counties for non-police officers.

It's a reminder that tensions in Baltimore, which would certainly have been exacerbated by a failure to press charges, could still similarly be inflamed by the results of any trial.

On Wednesday, the country marked the 23rd anniversary of the start of the Los Angeles riots of 1992. Those erupted not when news of the beating of Rodney King first emerged, but when the four officers charged in the attack were found not guilty by a largely white jury. For those seeking accountability in Gray's death, the unusually sweeping charges are a step in the path, not the final destination.