The video clearly shows the cop dropping the taser next to the body.
The two things we do know is that the cop lied and the video tells the truth.
Just curious, has it been confirmed it was a taser he dropped?
You can't tell from the video whether or not it was the Taser. It does appear that he drops something.
As Scott breaks away and starts running, an object is tossed back behind them onto the grass on the far side of the walkway. Slager then shoots Scott and comes over to him and handcuffs him. Then Slager jogs back across the walkway and appears to pick something up before returning to Scott, who is now being examined by the second officer. It is at that point that Slager drops an object at the scene, in the presence of the second officer.
Santana the videographer reports, "I remember the police had control of the situation. You can hear the sound of a Taser ... I believe [Scott] was just trying to get away from the Taser."
So, it seems likely the object Slager retrieved was the Taser, and that he felt that having it found arguably in possession of the deceased would better serve his story.
It would also be interesting to hear the second officer's account before he learned of the video.