An attorney defending the police officer who shot Walter Scott hammered the state’s probe into the shooting Wednesday, dissecting the pieces of evidence that investigators missed and others they failed to test.

And, at times, prosecutors joined in the criticism.

A crime-scene investigator from the State Law Enforcement Division was grilled by the defense when she testified for the prosecution in former patrolman Michael Slager’s murder trial.

To fend off a view that evidence-gathering had been mishandled, prosecutors suggested that SLED had decided early on that the officer’s use of force against Scott was legitimate, explaining why some tests were not done.

“It sounded like that at the beginning,” SLED Special Agent Jamie Johnson said.

The agency did not analyze Slager’s Taser section by section for traces of DNA that could indicate who had touched it. The officer had alleged that Scott grabbed the device during a fight before he opened fire. Instead, the whole stun gun was scrutinized, revealing DNA from both men and failing to show where it came from.

It wasn’t until later, when a video of the shooting emerged and raised fresh questions, that the state agents sought evidence to test the officer’s self-defense story, Chief Deputy Solicitor Bruce DuRant asserted. But Johnson brushed off the idea that SLED throws probes into police shootings in officers’ favor.

“That’s not what we do,” she insisted. “Our investigation is not slanted one way or another.”

Brought out during cross-examination, the revelations marked a significant development in Slager’s defense before any witnesses for his side were called. The difficult task that remains for the defense is explaining each of the eight shots that Slager fired at Scott. Five of the bullets hit Scott, and a forensic pathologist who did an autopsy on his body testified Wednesday that at least one of the wounds was fatal.

But even the pathologist was challenged by the defense on her definition of the human back. All five bullets struck Scott from behind, though they were closer to his right side than his spine.

"But they were in the back,” Dr. Lee Marie Tormos said of the wounds.

‘Wanted Mr. Scott’s DNA’

Johnson was the second state crime-scene expert to take the stand since testimony began a week ago, but her account sent a different message about the agents’ initial impressions. On Tuesday, her former supervisor testified that Scott’s wounds gave him early suspicions that called the officer’s account into question, and the agency's chief said soon after the shooting that the two didn't add up.

Some of the key tests would be done in the three days between Scott’s April 4, 2015, death and the public surfacing of the video, hampering SLED’s ability to do later examinations and vet Slager’s version. Other evidence at the site, including two bullets, was simply overlooked.

Slager pulled over Scott’s car that day for a broken brake light. Scott ran, and Slager tried to subdue him with a Taser. Slager said Scott grabbed the stun gun during a struggle on the ground and pointed it at him. He then fired in self-defense, he said.

The video showed Scott turning and running away before the shooting began.

Johnson knew early that the Taser would be crucial evidence. But she testified Wednesday that she decided on her own to swab for DNA across the entire Taser because it boosted the likelihood that some DNA could be found. Traces of touch DNA, or tiny skin particles, from both men were discovered, but Johnson didn’t pinpoint their location on the Taser.

“You all wanted Mr. Scott’s DNA to be on the there, didn’t you?” DuRant said in questioning Johnson on any early biases in the case.

The judge said the witness did not have to answer.

‘It wasn’t complicated’

It was defense attorney Andy Savage who spent the most time peppering Johnson on her agency’s investigation.

In hearings before the trial, prosecutors and Scott’s family had accounted for the DNA on the Taser by pointing out that Slager had jabbed the device into Scott, hoping to jolt him with electricity during their confrontation. Scott's DNA could have transferred then.

But the part of the Taser that delivers the shock was never tested.

“I don’t recall having swabbed the business end of the Taser,” Johnson said.

“You know that the greatest quantity of DNA found on that Taser was Walter Scott’s, correct?” Savage asked.

“I didn’t know whose quantity was greater,” she said.

Savage’s questioning affected the jury and courtroom observers. Some jurors looked down and scribbled on notepads. A loved one of Scott’s dabbed her eyes.

SLED also never looked for fingerprints on the Taser. Most surfaces on the weapon just do not capture such evidence well, Johnson explained while acknowledging that it’s still possible to find prints.

“Possibilities only turn into realities when (evidence is) examined,” Savage said, “and this was not examined.”

Still more evidence, like the wires that a Taser sends out when it's fired, were not examined at SLED.

“I’m not a Taser wire expert,” Johnson said.

“What are you an expert in?” Savage asked.

Savage’s own private investigators found the two bullets that SLED had missed along an alley next to the vacant lot where Scott was killed. He told Johnson that they unearthed the evidence with a toy metal detector.

“The point is,” the lawyer said, “it wasn’t complicated.”

‘Not evidence’

While jurors already have seen the video of Scott’s death and another of officers tending to him in the aftermath, Tormos said her autopsy indicated that he had been running away when he was shot.

The bullets hit Scott at a slightly sideways angle, from right to left. Jurors saw pictures of each wound. Sitting in the gallery, Scott’s mother bowed her head as an image flashed on a screen. One juror flicked at his own ear when Tormos described the bullet that grazed Scott’s right ear.

He had other injuries: bruises on his cheeks, his head, a wrist and a hand; scrapes on his back and an arm. His fingernails were bloodied. It was apparent that Scott had gotten into a struggle on the ground and fallen at some point, Tormos said.

Slager also had scrapes and cuts on his hands and legs.

“He actually bled on (paperwork) that he filled out,” Johnson, the crime-scene expert, testified.

Testimony eventually turned to what the defense has called a key part of their case: that Scott’s drug use fueled his behavior on the day he died.

But presiding Circuit Judge Clifton Newman would not let the defense question a forensic toxicologist about how cocaine in Scott’s blood could have caused “excited delirium” and a rash resistance to authority. The judge also barred Scott’s positive cocaine test four months before the shooting from being shown to jurors.

Still, the defense managed to ask the prosecution's toxicologist, Demi Garvin, whether the drugs could have cause aggression in Scott. Garvin pinned Scott’s cocaine level at 36 nanograms per milliliter; but an average impaired driver's is 87. Scott’s body also showed a level of benzoylecgonine, or broken-down cocaine, that was 1,300 nanograms per milliliter, higher than some people hospitalized for use of the drug.

But Garvin resisted questioning that implied the testing could explain how Scott acted that day, and without the jury in the courtroom, the judge said he would tell the panel before it weighs a verdict in the coming weeks “that questions asked by the attorneys is not evidence.”

Reach Andrew Knapp at 843-937-5414 or twitter.com/offlede.

Andrew Knapp is editor of the quick response team, which covers crime, courts and breaking news. He previously worked as a reporter and copy editor at Florida Today, Newsday and Bangor (Maine) Daily News. He enjoys golf, weather and fatherhood.