The following article was originally published in the Texas Observer. To read more Texas Observer articles click here.

On October 24, the Houston Police Department announced the results of its yearlong investigation into the shooting death of Brian Claunch, a mentally ill double amputee killed by an officer last September after refusing to drop a pen. HPD cleared the officer, Matthew Marin, of any wrongdoing.

That may not come as a surprise, since HPD hasn’t found a single police shooting unjustified in at least six years. Between 2007 and 2012, HPD officers fatally shot 109 people and injured another 111. All those shootings were found justified. (For the full story on HPD shootings and beatings, read the Observer investigation here.)

But some expected this case to be different. Claunch was wheelchair-bound and had one arm and one leg. He was definitely aggressive—officers were on the scene because Claunch was agitated, shouting threats and demanding soda and cigarettes—but he was also obviously disabled. HPD reports that Claunch backed an able-bodied officer into a corner and slashed at her with a shiny object, prompting her partner, Matthew Marin, to shoot him. But it’s difficult to visualize Claunch simultaneously moving effectively and posing a serious threat with one arm, even if he had been holding something more deadly than a ballpoint pen. Claunch was also known to be mentally ill; he lived at a small group home for men with mental illness. For all these reasons, some observers expected this shooting to be considered unacceptable.

And at first, it seemed like it would be. Houston’s police chief issued a statement two days later calling Claunch’s death “tragic” and announcing that he’d asked the FBI to investigate. CNN picked up the story, as did The Guardian and The Huffington Post. The Houston Chronicle issued a scathing editorial, stating plainly, “If an officer cannot deal with a mentally ill double amputee waving a silver pen without resorting to deadly violence, then he probably should not be a police officer.” It concluded, “HPD must explore serious reforms. Houston should accept nothing less.”

Yet serious reforms did not come, and Marin is still a police officer. This is despite the fact that Marin had an extensive rap sheet even before Claunch’s killing. It’s notoriously hard to punish an HPD officer (read the Observer’s investigation of HPD’s discipline system here) but Marin racked up 18 disciplinary actions in just five years on the force. These included untruthfulness, misconduct, an at-fault accident, failure to report for duty, failure to complete training, improper police procedure three times and “conduct and behavior” twice. Internal Affairs also cleared Marin in an alleged assault in 2008, and it found no fault in his fatal shooting of a knife-wielding man in October 2009. That suspect had already killed a neighbor and injured his girlfriend when Marin shot him. After killing Claunch, Marin requested a transfer to HPD’s property room, where he remains.

Claunch, too, had a history. The owner of the group home where he lived said Claunch was aggressive but not necessarily violent. Claunch suffered from schizophrenia and bipolar disorder, heard voices and suffered brain damage in the train accident that took his left limbs. After repeated hospitalizations, Claunch became a ward of Harris County in 2003 and was placed in a guardianship program where he stabilized for a few years. But between 2006 and 2010, he stopped taking his medications and was in and out of jail on drug and trespassing charges. An HPD report from 2006 indicates Claunch became aggressive during a trespassing arrest and had to be subdued by a Taser.

Al Tribble, an FBI agent who investigated Claunch’s death, says that record makes a difference. “[If] you get somebody that’s a choir boy, that’s never had a problem in their life…and you’ve got all this force, there’s something wrong with that picture,” he says. “But someone that is prone to violence, that is violent, that’s written down… ‘Hey we had to use these methods to subdue him,’ the finding’s going to be that [the use of force] wasn’t cruel and unusual and it wasn’t excessive.”

The FBI investigation was one of three separate determinations made about Marin’s actions. A grand jury declined to indict Marin in June, HPD has now cleared him, and while the Justice Department has not announced closing the case, Tribble says the FBI’s findings have been sent and he expects no indictments.

Tribble can’t comment on Claunch’s case directly, but he says one reason FBI indictments are so rare is that investigators must prove the officer willfully intended to deprive a citizen of his or her rights. “What we mean by that is, did the officer do something that they knew was wrong, and do it anyway, and do it intentionally with malice?” Tribble says the FBI looks at an officer’s Internal Affairs record, analyzes traffic stop data and interviews associates to detect animus. But still, he says, willful intent is “a very, very difficult component to prove.”

An officer’s mindset is also central to grand jury investigations. Tribble notes, “You’re talking about a grand jury that doesn’t know anything other than what is brought to them. They have to take that information and put themselves in that officer’s position and say, ‘Wow, was this reasonable? Was this unreasonable?’ That’s the question.”

HPD’s policy, too, centers on officer thoughts. The department’s general orders state, “The use of deadly force will be limited to those circumstances in which officers reasonably believe it is necessary to protect themselves or others from the imminent threat of serious bodily injury or death.”

For any of these groups to prove a violation, concrete evidence has to contradict an officer’s account of his beliefs. Brian Claunch died in a dimly lit room in the middle of the night. Evidence to prove Marin should have known better than to shoot him wasn’t there. Case after case after case closed.

As noted above, no police shooting of a Houston citizen has been found unjustified since at least 2007. And no Houston officer has been found guilty for a shooting in ten years, not since Arthur Carbonneau shot an unarmed 15-year-old, Eli Escobar, in broad daylight in 2003. Carbonneau was himself the first HPD officer to be tried for an on-duty shooting in ten years.

“What does it take to get an officer convicted?” Tribble says. “I hate to say this, but you need good evidence. If you’ve got videotape, sometimes it helps. But you know what? When you have videotape, that doesn’t always help because defense attorneys are going to say, ‘There was no sound. And because there was no sound, there are other variables afoot.’ So if you had video with sound, that’s going to help, but it’s going to take the first case where there’s excessive force, video and sound, and someone will come back acquitted, for folks to say, ‘What is it going to take?’”