Some legal experts are saying that in laying out the difficulties in making federal civil rights case against the two Baton Rouge police officers involved in the shooting death of Alton Sterling, acting U.S. Attorney Corey Amundson on Wednesday may have also pointed out the path for a state criminal investigation that now falls to Louisiana State Attorney General Jeff Landry.

After a nearly 10-month investigation, Amundson said, prosecutors and FBI investigators were not able to meet the high bar set in federal law: that Officers Blane Salamoni and Howie Lake II acted willfully and unreasonably and with a specific intent to shoot and kill Sterling July 5.

"Being reckless, escalating a situation that may have been de-escalated, those things are not a basis under the law for federal criminal civil rights prosecution," Amundson said in a news conference.

Pauline Hardin, a white collar criminal defense attorney in New Orleans and former state and federal prosecutor, said that unlike the federal willfulness standard for federal civil rights cases, state homicide statutes require differing levels of intent, ranging from first- and second-degree murder to negligent homicide.

Negligence, recklessness, overreaction, bad judgement — all are covered by the state homicide statutes, she and other experts noted.

"There is no willfulness, but there may still be recklessness and negligence. I think he was hinting at that," LSU criminal law professor Ken Levy said of Amundson's statements Wednesday.

"I think that's kind of where state investigation is going to go: Was it reckless or negligent," Levy added.

In a statement issued after Amundson's news conference, Landry said he would not comment on federal prosecutors' findings but said he has directed the U.S. Department of Justice to turn over their Sterling investigative materials, has appointed a prosecutor in his office to handle the case, and has asked Louisiana State Police to investigate.

Landry noted State Police already has a team that investigates officer-involved shootings, including the shooting of Christopher Few and slaying his 6-year-old austic son, Jeremy Mardis, in Marksville in November 2015.

"There is no other unit in the state with more experience or more expertise in the use of lethal force by law enforcement agents," Landry said.

Hardin added that Landry could ultimately bring the case to the East Baton Rouge Parish grand jury to review for possible charges, though no one in District Attorney Hillar Moore III's office could be involved. Moore recused himself and his office from the case last year because of his personal ties to Salamoni's parents.

Prem Burns, a former longtime lead prosecutor for former East Baton Rouge District Attorney Doug Moreau and for Moore, said federal prosecutors don't end up bringing charges in the vast majority of criminal civil rights cases involving officers' use of force because of the difficulty in meeting the willfulness standard.

Prosecutors would have had to disprove officers' explanation for their actions — that they believed Sterling was going for the .38 caliber revolver in his right pants pocket — and also shown that the officers intended to break the law and kill him.

"This is the highest standard in federal criminal law, willfulness," Amundson said.

At the news conference and in a statement, federal prosecutors went into detail about how a lack of evidence at critical moments stymied their ability to prove the elements of a civil rights violation.

They noted that at the second when Salamoni was struggling with Sterling's right arm and shouted Sterling was going for the gun, video recordings that have been publicized and that investigators have not made public do not show where Sterling's right hand was located.

Prosecutors added that the statements of two witnesses who claimed Sterling's right hand was not in his pocket are insufficient proof because of other inconsistencies in their statements and because parts of their accounts were contradicted by the video that does exist.

"In other words, we cannot establish that Mr. Sterling was not reaching for a gun or more accurately that the officers did not believe he was reaching for a gun and, therefore, cannot establish that the lethal force that was used was not unreasonable," Amundson said.

Because prosecutors can't show what the officers were doing was unreasonable or against the law, they also can't prove willfulness.

Some civil rights activists argue that the willfulness standard is too tough and is often the downfall of civil rights cases.

In a statement Wednesday, Sherrilyn Ifill, president and director-counsel of the NAACP Legal Defense and Educational Fund Inc., called the willfulness standard "deeply flawed" and one that frustrates the meaning of federal law "designed to protect against the deprivation of rights by officers of the state."

Burns, however, noted the U.S. Supreme Court set the willfulness standard in the mid-1940s and it has remained in place ever since.

Under state law, though, that standard doesn't apply.

Negligent homicide, for instance, would require a showing of just criminal negligence, Levy said. Manslaughter does require a showing of a specific intent to kill — Sterling was shot six times — but also that the slaying happened in a moment of passion, or what's called "hot blood."

Burns noted that hot blood can arise from a provocation.

"It would be like a person resisting arrest who is provoking them (officers). As a result, their blood did boil, and they get hot headed," Burns said.

Federal prosecutors Wednesday went through the series of events in which they said Sterling repeatedly refused to follow the officers' commands.

The experts suggested that if there is a state criminal case, the officers are likely to argue self-defense but even with the deference officers are normally afforded in split-second situations, a criminal case could be made.

Burns pointed to the recent conviction of Derrick Stafford, a former Marksville police officer and deputy marshal who also claimed self-defense, on manslaughter and attempted manslaughter counts. Stafford shot and injured Christopher Few and killed his 6-year-old autistic son during a confrontation stemming from an attempted traffic stop in November 2015.

A second law enforcement officer is facing charges in that case.

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