A judge declared a mistrial Sunday in the case of a man who admitted to a string of highway shootings — one of which killed a woman — but claimed innocence by reason of insanity.

The hung jury came after four full days of deliberations in the trial of Charles McCoy Jr., (search) charged with 12 shootings that terrified Columbus-area commuters over five months in 2003 and 2004.

Earlier in the day, jurors told the judge they voted twice on the issue of insanity and could not reach a unanimous decision. Two jurors sighed and had tears in their eyes when they were sent back to continue deliberations. The panel deliberated about an hour longer before declaring another impasse.

"We have no indication at this time that this will change," jurors told the court in a note read by the judge.

County Prosecutor Ron O'Brien (search) said he would retry McCoy, 29, who could have faced the death penalty if convicted of the most serious charge, aggravated murder, for the one death in the case. Gail Knisley (search), 62, the only person hit in the shootings, was killed Nov. 25, 2003, as she was being driven to a doctor's appointment.

If found innocent by reason of insanity, he would be committed to a mental hospital until a judge ruled he was no longer a danger.

"We are extremely disappointed in the outcome," said Knisley's son Brent, reading a brief prepared statement by phone. "If there's another trial and another trial and another trial, we will still be there."

McCoy's father, Charles McCoy Sr., thanked the jury for its work and said his family's thoughts were with his son and the Knisley family.

The case focused on two psychiatrists who disagreed whether McCoy met the legal definition of insanity: that a severe mental illness prevented him from knowing right from wrong.

The defense psychiatrist said McCoy was desperate to rid himself of humiliating voices in his head that called him a "wimp" for not standing up to mocking from television programs and commercials. He also said McCoy believed others could read his thoughts.

The prosecution's psychiatrist said that, despite the delusions, McCoy showed he knew his actions were wrong by steps he took to avoid capture, such as leaving for Las Vegas when his father turned McCoy's guns over to police. Investigators had learned about the weapons from a caller.

McCoy was arrested a few days later, on March 17, 2004.

During closing arguments, each side attacked the other's expert.

Prosecutors said the defense failed to prove McCoy did not understand his actions were wrong because their expert believed McCoy's story without checking it against the facts.

Defense attorney Michael Miller told the jury that prosecution expert Dr. Phillip Resnick focused only on McCoy's actions that indicated he was trying to elude authorities and ignored other signs he did not know his actions were wrong.

The shootings frightened commuters and residents for months, as bullets struck vehicles and houses at varying times of day and night and at different spots along or near Interstate 270, the highway that encircles Columbus.

Most of the incidents took place near an interchange of the interstate and a highway where about 77,000 vehicles travel a day on average.