>> reporter: there was a live demonstration including safety rules. >> this is part of training, as well, not to deploy a taser on somebody who is operating a vehicle or machinery. is that correct? >> yes. >> reporter: new evidence presented in court during the manslaughter trials of former police officer kim potter. focussing on department policy and taser training. potter is accused of shooting and killing daunte wright after she says she made a mistake pulling her gun instead of her taser. >> i shot him! oh my god. >> reporter: prosecutors showing why the former officer never should have confused her two weapons. >> i'm right handed, right hand dominant, i carry my hand on my right side and taser on my reaction side. >> so you carried your taser on your left side? >> yes. >> why do you carry it on the other side? >> that's how the policy has always been. >> reporter: these still images introduced in court tuesday show