WEST PALM BEACH, Fla. — The third day of trial for Semmie Williams Jr. began Tuesday morning at the Palm Beach County Courthouse.
Williams faces a first-degree murder charge in the death of 14-year-old Ryan Rogers, who was riding his bike near his home in Palm Beach Gardens in November 2021 when police said he was randomly attacked and stabbed to death by Williams, who had no ties to the community or the teen.
WATCH: Williams asks to be moved from cell due to 'sensitivity to electromagnetic frequencies'
Before the jury was brought in Tuesday, Williams asked to address the judge, saying he needed to be moved from his current cell because he has a "sensitivity to electromagnetic frequencies" that are coming from the guard's station. The judge said that will be discussed later.
Last week, Williams brought up claims that law enforcement is coming into his cell and taking documents.
The first witness called by the state was Jennifer Brashear, a former crime analyst at the Palm Beach Gardens Police Department and lead detective on the Rogers case. She says she got to scene around 9:15 a.m. on Nov. 16, 2021, about 15 minutes after Rogers' body was found. The crime scene was already roped off but she confirmed the scene had not been tampered with and was secured.
The defense objected to surveillance videos that were to be shown in court, specifically how the videos were authenticated. After review, the court found further authentication was not necessary.
Brashear testified about surveillance video of Williams on the day of Nov. 15, 2021, showing him at locations in Boynton Beach and Mangonia Park before Palm Beach Gardens. Brashear said surveillance video and a receipt from a Dollar Tree in Boynton Beach helped them work out a timeline from his purchases to Williams crossing paths with Rogers.
The state called Michael McCabe, a former deputy with the Palm Beach County Sheriff's Office who worked intake and transport. He said on Dec. 2, 2021, he came into contact with Williams for fingerprinting, and to make sure he understood the charges against him.
When McCabe asked if he understood the charges, he alleges Williams stated, "Yeah, I killed that mother (expletive) and I'll kill you too." The jury was shown surveillance video of a struggle between McCabe and Williams without audio.
On Friday, witnesses included Kelly Behke, a senior forensic scientist at the Palm Beach County Sheriff's Office. She testified to having conducted three rounds of DNA testing on the evidence in this case.
During her nearly two-hour testimony, she disclosed that Williams' DNA was also found on the headphones and sunglasses found at the crime scene.
Behnke also disclosed that both the suspect's and victim's DNA were found on a bloody bandana recovered inside Williams' backpack during his arrest.
Seth Kaufman, an occupational therapist, took to the stand Friday as a witness, who said he spotted a man who seemed out of place in the Mirabella neighborhood of Palm Beach Gardens on Nov. 16, 2021, the day that Rogers was found dead.
Also taking the stand on Friday was Miami-Dade County Deputy Sheriff Jonathan Grossman. He testified that after Rogers was killed, his agency received a request from the Palm Beach Gardens Police Department to locate Williams.
The state said earlier this week that it will be bringing in roughly 22 witnesses, including Rogers' family members.
The trial is now expected to end on Jan. 22.
