The family of a Florence police officer says they're not satisfied with Florence County's investigation into his death.

Scott Hemann believes the Florence County Sheriff's Office mishandled the investigation into the death of his nephew Matthew Clayton. In February, Clayton was shot to death at his Florence home. Clayton was an officer with the Florence Police Department, but was off duty that night.

Florence Police called the sheriff's office in to investigate. They charged Brady Johnson with voluntary manslaughter in Clayton's death.

But Hemann says, something just doesn't add up. "I mean every time we've looked at the different evidence, nothing adds up or makes any sense."

But the sheriff's office stands by the charge, saying Johnson did not intend to kill Clayton. "We know the family has some strong feelings about this case and we sympathize with them over the loss of Matthew. The truth of the matter is an investigation that's properly done follows evidence to a conclusion not start with a conclusion and then find evidence to substantiate," said Capt. Mike Nunn, Florence County Sheriff's Office.

Hemann says his family believes otherwise and did their own investigation. Hemann says they have state police documents that show Johnson was a confidential informant for the Florence County Sheriff's Office. "There's no question there's a conflict of interest," Hemann said.

He believes the sheriff's office should have called in the State Law Enforcement Division because Johnson had helped them in an unrelated steroid bust. The family sent a letter to SLED citing 39 problems with the sheriff's office investigation, along with four You Tube videos  (video 1, video 2, video 3, video 4) they made re-enacting what they believe happened the night of the shooting. "We did it for SLED and in doing so, SLED told us they would meet back with us to go over their findings."

SLED found no evidence the investigation was mishandled according to prosecutor Jimmy Richardson with the 15 Circuit Solicitor's Office out of Horry County. They're handling the case instead of the Florence County Solicitor's Office avoid any appearance of impropriety.

Richardson expects Johnson will plead guilty to a manslaughter charge. Hemann hopes to convince the judge at that plea hearing that the investigation was mishandled.

Johnson's hearing is set for Thursday. We'll let you know what happens.