As a criminal investigation, the case of ex-Los Angeles police officer Christopher Dorner is virtually over.

The rogue cop believed to have killed four people – including two law enforcement officers and the daughter of a third officer – took his own life at the end of a massive manhunt that ended with a fiery shootout in a cabin in southern California’s San Bernardino Mountains. There is no doubt about his responsibility for the string of killings nor any evidence that Mr. Dorner had accomplices who might have helped him evade capture for so many days.

But tough issues remain.

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Los Angeles Police Chief Charlie Beck has ordered an official review of Dorner’s charges that he was fired from the LAPD because of racism and corruption in the department. "I am aware of the ghosts of the LAPD's past,” Chief Beck said in announcing the review – a reference to the Ramparts scandal, the Rodney King riots, and other dark episodes in the department’s history.

Most civil rights advocates – including those who have butted heads with the LAPD in court over the years – acknowledge that the department has improved, particularly under Chief William Bratton and now Chief Beck.

“The LAPD is by no means a perfect police department. But it's a much, much better one than it was,” writes political journalist and Los Angeles resident Marc Ambinder on the news and opinion website “This Week.”

“Many, many, many bad police officers were forced out. Less than half of the LAPD is now white; the ranks of minority supervisors are growing,” Mr. Ambinder writes. “It is hard to find a major community group in L.A. that does not concede that the basic, street-level interaction between police officers and citizens of all ethnicities, genders, and sexual orientations has gotten much warmer, friendlier, and effective, even as they understandably point out exceptions.”

Still, suspicions about the circumstances of Dorner’s death – and the charges he outlined in his Facebook manifesto before he began his rampage – remain strong, especially among many in minority communities.

“Conspiracy theories surrounding the fugitive ex-policeman have only increased as people search for answers since he died on Tuesday,” the Los Angeles Daily News reports. “So-called ‘Dorner Truthers’ established an online presence since Dorner's fiery death inside a Big Bear cabin where he engaged in a shoot-out with police. They questioned everything from the wallet officials said they found with Dorner's I.D., to whether Sheriff's deputies burned down the cabin on purpose, to the possibility that Dorner might still be alive.”

Law enforcement officials deny such charges.

Based on a coroner’s report, they said Friday that Dorner had shot and killed himself during the firefight, and they strongly deny that the cabin in which the fugitive had holed up was intentionally burned down.

"We stand confident in our actions on that fateful day," San Bernardino County Sheriff John McMahon said at a press conference Friday.

Still, Sheriff McMahon acknowledged that officers did fire incendiary tear-gas canisters known as “burners” – but only after Dorner had refused to surrender and kept shooting an arsenal of military-style weapons he’d been trained to use as a policeman and naval reserve officer.

Another issue yet to be settled is who – if anyone – receives the $1 million reward pledged by Los Angeles Mayor Antonio Villaraigosa "for information that will lead to Mr. Dorner's capture."

So far, no one has claimed the reward, although one couple might be in a position to do so.

Jim and Karen Reynolds, in whose home Dorner is believed to have hidden for days, called in the tip that ultimately put police on the trail to Dorner's final location, ABC News reports. On Tuesday, the couple found Dorner at their home. He briefly held them captive, but they managed to escape and call in their tip.

But the biggest challenge for law enforcement agencies and Los Angeles area communities generally may be overcoming any lingering sense that Dorner – labeled by some as a sort of “Dark Knight” – is some kind of hero.

“Too many people online have portrayed Dorner’s actions as righteous retribution,” writes New York Times columnist Charles Blow (who is African American). “But nothing can change the fact that those actions are wrong. Fighting for justice is noble. Spilling innocent blood is the ultimate act of cowardice. Dorner is not the right emblem for those wronged by the system.”

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