COLUMBUS (AP) - The family of the only woman killed in a string of highway shootings attended the trial of the admitted shooter every day. They say that they'll be back for the next one, now that a mistrial was declared because jurors couldn't reach a verdict.

After two votes and urging from the judge to try again, the jury could not agree whether Charles McCoy Jr. was insane. The hung jury came after four full days of deliberations in the trial of McCoy, 29, charged with 12 shootings that terrified commuters over five months in 2003 and 2004.

County Prosecutor Ron O'Brien said he would retry McCoy, who could have faced the death penalty if convicted of the most serious charge of aggravated murder for the November 2003 shooting of Gail Knisley, the only person killed.

If no plea deal can be reached, a new trial will involve repeating more than two dozen witnesses, including one who lives three hours away in Pittsburgh.

It also means forcing Mary Cox to listen again on the witness stand as she hears her 911 call during her best friend's dying minutes. She was driving Knisley to a doctor's appointment when a gunshot pierced the door.

''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, who has remained stoic throughout the trial, stared straight ahead as jurors were dismissed Sunday. Earlier in the case, he cried only when his parents testified about the start of his mental illness.

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.

Franklin Common Pleas Court Judge Charles Schneider will meet with the prosecution and defense Tuesday to determine what happens next.

The jurors, who were first summoned April 8 and heard eight days of testimony, were escorted out of the courthouse at their request and did not comment.

Juror Bobby Collins, a retired police officer, said he was ''very disappointed'' when reached later by telephone. He declined to discuss deliberations. ''There will be another trial, and I don't want to taint that.''

If jurors would have accepted McCoy's plea of innocent by reason of insanity, he would have been committed to a mental hospital until a judge ruled he was no longer a danger.

Prosecutors and defense attorneys left open if negotiations would resume on a plea deal, but the two sides remain divided. O'Brien remains convinced McCoy understood what he was doing, and defense attorney Michael Miller, O'Brien's predecessor, said he believes ''with every fiber in (his) body'' that McCoy was insane.

The defense admitted McCoy was behind the Columbus-area shootings, plus about 200 acts of vandalism involving dropping lumber and bags of concrete mix off of overpasses. But his attorneys insisted he did not understand his actions were wrong because of delusions from his untreated paranoid schizophrenia.

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

Residents and commuters were frightened for months as bullets struck vehicles and houses at varying times of day and night along or near Interstate 270, the highway that circles Columbus. Most of the incidents took place near an interchange of the interstate and a highway where about 77,000 vehicles travel daily.

A bullet missed Edward Cable by about 15 inches a few days before Knisley was killed. The retired prison guard lives more than two hours south of Columbus in Lucasville but said he's ready to testify again.

''This guy needs to be responsible for what he did,'' he said. ''I'm convinced he knew exactly what he was doing every step of the way.''