Was the Sandra Bland arrest video edited?

In an effort to quell speculation on the circumstances surrounding the death of black woman Sandra Bland in custody Texas police have released a video showing her arrest, but the footage has raised as many questions as it has answers.

Bland was found dead in her cell on July 13 after being arrested during a traffic stop in a case that has led her family and supporters to dispute that she hanged herself with a plastic garbage bag, as authorities have said.

The police dashboard video shows a state trooper trying to pull Bland out of her car, then drawing his stun gun and threatening to "light her up" after she refuses to follow his order to put out her cigarette.

Ava DuVernay, the award-winning director of Selma, took to Twitter after the footage was released to say that glitches, audio cuts and loops in cloud movement all suggest the video has been edited.

The LA Times has weighed in say they too found parts of the 52 minutes' worth of footage have "clearly been doctored", citing images of a man leaving a truck at 25.05 and a white car passing by at 32.37 that have been looped, and the fact that the clip's audio appears to end more than a minute before the video does.

Police have also released footage from the corridor outside Bland's jail cell which they claim show nobody entered the room 90 minutes prior to her death, although the tape contains gaps because police say the camera is motion activated.

Bland's death in custody has provoked anger in the US and is now being treated as a murder investigation by prosecutors, in spite of the coroner's original verdict of suicide.

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