This article is from the archive of our partner National Journal

Eric Garner's death was ruled a homicide by the medical examiner's office. But Daniel Pantaleo, the white police officer who put the 43-year-old black man in the choke hold that killed him, will not face legal repercussions. A Staten Island grand jury decided on Wednesday not to bring criminal charges against him.

The episode rings familiar. Just last week, a grand jury decided not to indict Darren Wilson, the Ferguson police officer who shot and killed Michael Brown in August, setting off waves of protests throughout the country.

The lingering question: Why is it that neither of these police officers—who both killed unarmed black men—is facing at least a trial? A part of the answer lies in the laws that govern use of deadly force, which give officers discretion in determining when they feel their lives and the lives of others are in danger. But another part lies in the workings of the grand jury system, which tends to work in favor of law enforcement.

Bottom line: Police killings occur somewhat regularly, police-officer arrests are relatively rare, charges of manslaughter or murder against police officers who kill people are rarer still.

Grand juries are not meant to determine a defendant's guilt or punishment. Instead, they decide whether there is probable cause to bring charges against a defendant. It's the trial before the trial.

But not really.

"Grand juries are a secret proceeding," says Terry Gilbert, a civil-rights lawyer in Cleveland and a board member of the National Police Accountability Project. "It's not meant to be a trial where all the facts are presented and the witnesses are subject to intense cross-examination. [A trial] is the forum that gets closer to the truth."

There are no judges at grand juries, just one lawyer, the prosecutor, who is seeking an indictment. Prosecutors present evidence and witness testimony to determine whether there is probable cause to bring charges against a defendant. Then, the jurors vote.

There is no case from the defense, which is why the odds are usually stacked in the prosecutor's favor. And when police officers are the defendants, that can be problematic, Gilbert says. Prosecutors can be reluctant to investigate the police departments they work with on a regular basis to build other cases.

"The outrage that we see in Ferguson and now in New York raises the question whether the system is protecting white police officers over black victims," Gilbert says. He says that appointing an independent prosecutor, rather than a prosecutor from that jurisdiction, to lead a grand jury investigation of police officers could eliminate potential conflicts of interest.

According to the University of Dayton School of Law, 48 states and the District of Columbia use grand juries; Connecticut and Pennsylvania do not. Twenty-three states and D.C. require grand jury indictments for charges of certain crimes, and 25 states make the use of indictments before a trial optional. In states where indictments are not required, probable cause can be determined at a preliminary hearing, during which a judge hears arguments from both sides before deciding whether a case goes to trial.

At the federal level, it is extremely rare for a grand jury not to grant an indictment for a case. Between October 2009 and September 2010, U.S. prosecutors sought indictments in 193,000 cases. Grand juries refused to indict in just 11 of them.

Better data would yield a clearer picture on whether justice is being served. Exact numbers on how many people are killed each year by police don't exist. According to the work of Phil Stinson, a Bowling Green University criminologist, between 2005 and 2011, there were 664 arrests of police officers due to their conduct with a gun. There aren't data on how many were convicted. But in his analysis, Stinson found that at least 41 were charged with murder or manslaughter. In that same time period, the FBI reported 2,718 justified homicides at the hands of law-enforcement officials.

"We're seeing too many instances where people do not have confidence that folks are being treated fairly," President Obama said after learning about the Staten Island grand jury's decision. "In some cases, those may be misperceptions, but in some cases, that's a reality."

Bottom line: Police killings occur somewhat regularly, police officer arrests are relatively rare, charges of manslaughter or murder against police officers who kill people are rarer still.

This article is from the archive of our partner National Journal.

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