WATCH: Sentencing May Come Wednesday In Charleston Police Shooting Case

Attorneys for a white former North Charleston police officer who shot and killed a black motorist during a routine traffic stop in 2015 are expected to wrap up their defense Wednesday morning, believing they’ve successfully shown their client, Michael Slager, committed manslaughter, not murder, when he shot Walter Scott to death.

That determination will be made by U.S. District Judge David Norton, who could hand down his sentence as early as Wednesday afternoon. Slager, who has been held in solitary confinement since he pleaded guilty in May to violating Scott’s civil rights, faces a sentence of anywhere from time served to life behind bars.

A pre-sentencing report, which determined Slager’s underlying offense to be voluntary manslaughter, recommended a term of between 10 and 13 years in prison. But that report is just a suggestion. The ultimate decision is Norton’s and his alone.

The sentencing hearing, which got underway on Monday, is the latest and presumably final chapter in a story that began on April 4, 2015. It was on that warm and sunny spring Saturday afternoon that Slager pulled Scott’s car over for a broken brake light.

A dashcam video shows a calm encounter between the two men, with Slager asking Scott for his license and registration, and then walking back to his police cruiser. It was at that point that the 50-year-old motorist ran from the scene.

Slager caught up with Scott in a nearby neighborhood park. The former officer’s fate hinges entirely on what Norton believes happened next.

Slager claimed he shot Scott after he and Scott fought and the fleeing man grabbed the officer’s Taser. Slager said at that point he feared for his life and opened fire. But a cellphone video shot by a passerby doesn’t show the two men fighting. What it does show is Slager shooting Scott several times in the back when the motorist was already several feet away from him.

On Tuesday, the second day of testimony at the sentencing hearing, a forensic expert presented by the defense said Slager fought Scott and both men wound up on the ground where the officer warned, “Let go of the Taser before I shoot you.”

Grant Fredericks’ testimony came on the day the prosecution rested its case at the hearing.

A second defense expert, David Hallimore, testified that when filtered and enhanced and layered three audio recordings of a cell phone video, the officer’s body microphone and dispatch recordings he could hear Scott say “F-the police” and Slager warning him to let go of the Taser.

None of these statements could be heard when the audio was played in the courtroom, by Hallimore said he could hear those exchanges when listening with high quality headphones.

He also assured the court no phases were suggested to him, and that his laboratory determined what the spoken words were without outside influence.

Referring to Slager’s initial call for backup as Scott began running from the traffic stop, Hallimore said there is notable stress in Slager’s voice.

“When he says, ‘step it up,’ the other officers would perceive this to mean that he was in real trouble. To me you can hear fear in his tone,” Hallimore testified.