Truman Pkwy double homicide trial: closing arguments wrap, jury to deliberate

SAVANNAH, Ga. (WTOC) - Closing arguments concluded in the trial of Derek Johnson, a Savannah man accused of killing 19-year-old Shaliyah Collins and bystander Phillip Mock in a 2023 shooting on Truman Parkway.

The jury is set to begin deliberations following the conclusion of arguments from both sides, which wrapped up around 5:45 p.m. Thursday night.

Defense targets ex-wife’s credibility

Johnson’s defense attorney, Kaitlyn Walker, used the full two-hour window allotted for closing arguments to raise doubt about Johnson’s guilt.

Walker argued that Johnson’s ex-wife, Lakia Johnson — who testified she was threatened at gunpoint to help Johnson throw a victim’s body over an overpass — should be treated as an accomplice or even considered a possible shooter herself.

Walker also argued that Lakia Johnson, or any of her three sons, could have been the shooter instead of Derek Johnson.

Motive and video evidence challenged

Walker pointed to Derek Johnson’s son — Collins’ boyfriend — as someone with motive, while arguing Johnson had none.

See testimony from the son: www.wtoc.com/2026/07/08/truman-pkwy-double-murder-trial-begins-with-emotional-testimony-crime-scene-photos/

“There are many people that have motive here that Derek didn’t have,” Walker said. “And the state will correctly tell you they don’t have to prove motive. But ask yourselves, for proof beyond a reasonable doubt, don’t you want to know why something this horrific happens? So no, they don’t have to prove it beyond a reasonable doubt, but you decide how that affects the competency of the evidence they provide.”

Walker also challenged surveillance video showing a car registered to Johnson pulling up to a Walmart to pick up one of the victims, arguing it was difficult to identify who was behind the wheel, but it was obvious it was a man.

“The state’s going to get up and say, certainly this is Derek Johnson in this vehicle,” Walker said. “Does the figure in driver’s side clearly look like Derek?”

Defendant declines to testify

Johnson chose not to testify before closing arguments began. Walker addressed the jury on that point directly.

“Derek never has to testify,” Walker said. “No one in this country does. Can’t consider that in your analysis.”

Walker also noted that Lakia Johnson lied to detectives the first time they questioned her, waiting until a second interview to tell police what she said she witnessed the night of the shooting.

State defends ex-wife’s account

Prosecutors pushed back on the defense’s characterization of Lakia Johnson, arguing she lied to detectives initially because she had been threatened — for both her life and the lives of her sons — the night before police came to her door.

Prosecutors said that 17 hours after witnessing the double homicide, Lakia Johnson told detectives everything.

They also said she lied in part because when detectives arrived, her son — who is also the victim’s boyfriend — did not yet know his girlfriend was dead.

Prosecutors said Lakia Johnson also cited fear and the fact that Derek Johnson had access to her children as reasons she initially withheld information.

Witness described as still traumatized

Prosecutors told the jury that Lakia Johnson remains so fearful of Derek Johnson that she became visibly upset during trial when his defense attorney mentioned the new city she had relocated to — reacting to the fact that he now knows where she lives, three years after the shooting.

Physical evidence addressed

Chatham County prosecutor Matthew Schlager pointed to hydrogen peroxide purchased the day after the shooting.

Lakia Johnson said her ex-husband bought it to clean his clothes before disposing of them. Prosecutors also suggested it could have been used to treat two scratches on Derek Johnson’s arm.

Schlager noted there was no DNA evidence linking Collins to the scratches, as only her boyfriend’s DNA was found under her fingernails. Prosecutors explained that was consistent with the two living together and having been sleeping together the night before her death.

Prosecutors: Johnson fled to Florida after killings

Schlager argued the evidence points to Derek Johnson, and that when Johnson realized he could not avoid detection, he fled to Florida, where he was arrested.

WTOC told you in our previous coverage how prior to the trial, the judge ruled to keep a video out of the trial that showed immediately after Derek Johnson was arrested on two murder warrants in Florida, he fell asleep in the back of the patrol car.

As of 6 p.m. Judge Lisa Colbert is giving the jury directions on which charges they will decide on and why.

We will keep you updated when we have a verdict.