‘Puzzle pieces’ of evidence show Riverview man killed daughter, 13, prosecutor says

After his 13-year-old daughter Janessa’s decomposed body was discovered in a Hillsborough County nature preserve in July 2017, Nahshon Shannon spoke tearfully at a memorial, recalling the day the girl was born.

“I was so excited to see my daughter, my first child,” Shannon said at the memorial at Rodgers Middle School in Riverview later that month. “There was nothing more beautiful in this world.”

Three months later, Shannon was arrested on charges related to the girl’s death. On Monday, Shannon’s trial finally began in a Tampa courtroom.

In an opening statement, Hillsborough Assistant State Attorney Jessica O’Connor outlined evidence that she called “puzzle pieces” that will convince the 12-member jury that Shannon, 44, is guilty of first-degree felony murder and aggravated child abuse.

On July 1, 2017, a Saturday, Nahshon Shannon picked up Janessa from her mother Michelle Mosley’s house in Bradenton. He was driving a black Jeep Cherokee. Janessa Shannon lived at her father’s home on Cocoa Beach Drive in Riverview at the time because he had primary custody, and Mosley visited with her on weekends.

“When Janessa Shannon got into the Jeep Grand Cherokee, that was the last time she saw her daughter alive,” O’Connor said.

When Shannon left Mosley’s house, he texted his girlfriend, “I need you to go to your place, I need to deal with Nessa,” O’Connor said.

On July 2, around 6:08 p.m., Shannon sent his girlfriend a message saying he’d just checked Janessa’s room and she wasn’t there.

“He does not report her missing to the Hillsborough County Sheriff’s Office until July 3, the next day, at 12:58 p.m.,” O’Connor told the jury.

The report set off a frantic search for the girl. Her severely decomposed body was found on July 12 in a black plastic garbage bag in a shallow grave in a secluded area of the Triple Creek Nature Preserve off Balm Boyette Road in Riverview. The preserve, O’Connor told the jury, is a roughly 13-minute drive from Shannon’s home at the time.

The Hillsborough medical examiner found multiple areas of bleeding on the back of Janessa’s head and in her neck muscles that were “textbook” indicators of manual strangulation, O’Connor said. The autopsy also showed bleeding in an arm and the torso. The death was ruled a homicide from blunt force trauma.

Dr. Erin Kimmerle, a forensic anthropologist and associate professor at the University of South Florida, also analyzed the remains and found two fractures just above two of Janessa’s teeth, O’Connor said. Kimmerle also noted that a top and bottom tooth were chipped — consistent with blunt trauma below the chin in an upward direction — and that the girl’s nose had been fractured. Kimmerle also found a fracture on the back right side of her skull.

“All of these were inflicted on her before her death,” O’Connor said.

Toxicology tests showed the girl had alcohol and cocaine in her system that had been ingested within six hours of her death.

Two different species of insect were collected from the girl’s body, one that had colonized on July 4. That showed the girl’s body had been there since at least that day, O’Connor said.

Investigators with the Hillsborough County Sheriff’s Office collected a screw and some soil samples from the scene. In searching Shannon’s home, investigators found in the garage a Fiskar shovel that had been “modified” with additional holes, and that two screws were about to fall out. The Florida Department of Law Enforcement analyzed the screws on the shovel and the one found at the scene and determined they were the same type, and had “absolutely identical” chemical compounds, O’Connor said.

Investigators also found a plastic bag in Shannon’s Jeep that contained a small amount of soil. The chemical makeup of that soil was a 99.9% match to soil taken from the grave, O’Connor said.

Shannon’s private defense attorneys, William Bennett and Bjorn Brunvand, declined to make an opening statement.

Michelle Mosley, Janessa’s mother and the state’s first witness, testified that Nahshon Shannon showed up in his Jeep that day to pick up Janessa at Mosley’s request. She said her daughter was still wearing a choker necklace she’d worn during a trip to the beach earlier that day.

Mosley testified that Shannon looked “angry” when he left Mosley’s house because Janessa had snuck out of Mosley’s home the previous night, and that Janessa looked “scared.”

Shannon, dressed in a dark suit and blue tie, looked on from the defense table. He has been in a Hillsborough County jail, held without bond, since his arrest.

At the time of Shannon’s arrest, Hillsborough sheriff’s officials said he killed his daughter during an argument. Shannon previously told a Times reporter that Janessa ate dinner July 1, then went to her room. When he checked on her the next day, she was gone. He said he assumed she was upset and had gone for a walk. When she hadn’t returned by July 3, he said, he reported her missing.

The trial is scheduled to go through next week.

Times photojournalist Ivy Ceballo contributed to this report.