"Citizen videos" spread online showing BART police officer shooting unarmed man to death

(Warning, explicit content: the video below shows a man being shot to death).

In the early hours of New Year's Day, 27-year-old BART police officer Johannes Mehserle shot and killed 22-year old Oscar Grant. A number of people who were riding the BART train that night witnessed the shooting, and shot video or photos on handheld cameras or phones.

The victim's family filed a lawsuit for $25 million.

Five days after the shooting, the accused officer still has not given a statement. He is said to be have received death threats and authorities are apparently moving him from place to place to protect him from harm.

Some people are speculating the shooting may have been an accident -- the officer may have grabbed his gun by mistake because he thought he was instead grabbing a Taser device. That argument is quite hard to understand. The weapons are so different.

From SF Chronicle article, to that point:

[Use-of-force training and research firm founder Bruce Siddle] said changes in how the brain processes information in a stressful situation might have led the officer to mistake the butt of his service weapon for the Taser. But other experts found the idea that the shooting resulted from such a mix-up hard to believe.

"That's as reflexive as you getting in on the driver's side of the car (instead of) the passenger side if you want to drive it," [Florida criminologist George] Kirkham said. "There's no remote similarity to a conventional firearm. ... The Taser is just like apples and oranges."

The fact that so many videos and images are surfacing in this case is significant, because each set of images provides a different view of the killing, with different visual information.

From that same SF Chronicle article:

Roy Bedard, who has trained police officers around the world, advanced a different theory after his first viewing of the video: that the shooting was a pure accident, a trigger pulled because of a loss of balance or a loud noise.

But in an indication of how the videos might move the investigation, Bedard reached a different conclusion after viewing the shooting from a different angle.

"Looking at it, I hate to say this, it looks like an execution to me," he said. "It really looks bad for the officer. ... We have to get inside his head and figure out what he was thinking when he fired the shot."

Other places this story is showing up: BART Police (in Oakland) murdered a man on NYE.
Here is one video (nsa.org).
Here is another released by a Bay Area CBS affiliate -- first, we see the entire, raw footage a 19 year old eyewitness shot on her camcorder, then we hear her explain what she saw and experienced -- she says a female BART police officer tried to forcibly confiscate her camcorder.
Here is still another video (YouTube).