CLAY COUNTY, Fla. -- Prosecutors set an accused killer free after determining that he acted in self-defense when he shot and killed a 25-year-old woman last year.

Janie Johnson died at Shands-Jacksonville Medical Center the morning after she was shot five times inside the Grove Park Lane home of Michael Wierer.

Clay County Sheriff Rick Beseler said he's stunned by the state attorney's decision to release Wierer.

The sheriff admits not all of the facts of the case are clear cut, but said he wishes prosecutors would have let a jury decide Weirer's guilt or innocence.

Top prosecutor Dan Skinner said he dropped the case in part because of the way police handled the investigation.

One key fact that both men agree on is that on Jan. 19, 2007, Wierer shot and killed Johnson. However, why it happened and the recent dismissal of charges has prosecutors and the sheriff pointing fingers at each other.

A police report from the day of the shooting states that Wierer admitted to shooting Johnson, an alleged prostitute he had known for months, multiple times because she would not leave his home.

Wierer also told detectives that Johnson was not armed and was hiding when he shot her. He was arrested on a charge of murder.

Sixteen months later, Wierer is a free man. The state said in its disposition that there was insignificant evidence to warrant further prosecution of Wierer and that there was an improbability of conviction at trial.

Wierer has contended since the beginning that he opened fire due to self-defense and that Johnson had tried to rob him.

In their disposition, prosecutors also said Wierer changed details of the incident throughout his interview and had previously called police to say Johnson forced him to withdraw money from his bank.

In response, Beseler released a letter criticizing the lead state attorney, accusing him of collusion with the defense.

The sheriff said, “The fact is Mr. Wierer had been engaging the services of the victim as a prostitute for the previous year or two and was a regular customer … The interior of the home was in disarray because, according to Wierer, the victim ran around trying to hide under furniture as he fired multiple rounds at her.”

The sheriff also cited a letter from Wierer’s attorney Bill Sheppard asking for dismissal because of police inconsistencies.

“I was stunned when Mr. Skinner almost verbatim listed those same defense generated arguments as justification for dropping charges, leading me to wonder whose side is the prosecutor on,” Besler said in his written statement. “At the very least this case, which admittedly has some troubling aspects, was deserving of presentation to a jury to decide the outcome.”

He said by dropping the charges, “a killer has been released into our community.”

The prosecutor and Wierer’s attorney both said that several previous police reports were changed by deputies in the sheriff’s department. The sheriff said that was only done to comply with Florida Department of Law Enforcement requirements for crime reporting statistics.