The defense has opened its case in the murder trial of Michael Slager, the white former South Carolina patrolman charged in the shooting death of an unarmed black motorist.

Slager is charged in the April 2015 shooting of 50-year-old Walter Scott as he ran from a traffic stop. Cellphone video recorded by a bystander shows Scott being shot five times in the back.

The defense contends the two men struggled and Scott got hold of the officer's Taser before the shooting.

The prosecution rested late Wednesday after calling 32 witnesses over nine days.

The first defense witness was an audio expert who played enhanced audio from Slager's uniform microphone in which the officer warns Scott he is firing his stun gun.