SPRINGFIELD, Mo. (AP) _ Jon Feeney was so pleased with the gift he'd bought for his 17-month-old daughter that he showed it to his high school chemistry students.

``It was a pop-up book,'' recalled one of them, Debbin Phillips. ``I just remember him reading the book to the class.''

It's uncertain, though, whether young Jennifer ever got to enjoy her present. Within two days, the toddler was found dead along with her brother, 6-year-old Tyler, and 36-year-old mother, Cheryl.

Her father is accused of strangling her with a shoelace and beating the life from her brother and mother with a pipe. The state is seeking the death penalty on three counts of first-degree murder; the trial begins Tuesday.

Feeney, 36, claims he was at a teachers' conference at the Lake of the Ozarks, about 90 miles northeast of Springfield, when his wife and children were killed Feb. 26, 1995.

Thus far, the state has stumbled in trying to gather evidence to the contrary.

In the 14 months prosecutors took to get an indictment, Feeney lived in his home, repeatedly walking through the murder scene. An insurance investigator found Feeney was not at fault in the deaths, allowing him to collect insurance money for 300 items he said were stolen in the attack.

Assistant Greene County Prosecutor Darrell Moore acknowledges the case is not clear-cut. In numerous pretrial hearings, no mention has been made of any physical evidence linking Feeney to the crime scene, and Moore has said no witness puts Feeney in Springfield around the time of the slayings.

But there was a witness when the grand jury handed up its indictment in April. That man, a convenience store clerk named Ron Gann, is certain to play a central role in the trial, which is expected to last two weeks.

Defense attorneys initially wanted a judge to suppress Gann's testimony. Under oath, he claimed to have sold gas to a man resembling Feeney in the early morning hours after his family was killed. Gann also said he remembered Feeney's car: a red Mustang convertible.

Gann's story _ through depositions, police interviews and grand jury queries _ was pocked with inconsistencies. Nevertheless, Judge J. Miles Sweeney ruled Aug. 21 that Gann could testify and the jury would decide whether to believe his story.

Then, a twist:

The defense found time sheets that showed Gann was not even working during the hours he was supposed to have waited on Feeney.

It was a blow to the prosecution, which lost its only witness. And it was a coup for the defense, which plans to call Gann to the stand to highlight problems in the investigation.

The prosecution case now seems to rest on character assault. The state is expected to call witnesses who will testify Feeney had extramarital affairs and was not an attentive father.

Neither Moore nor lead defense attorney Shawn Askinosie could comment on the trial because of a gag order imposed last week by the judge. But that did not stop residents from buzzing about the case, which many people have called Springfield's ``Simpson trial.'' The local cable station said last week it would broadcast the trial live using a feed from Court TV.

That news was not welcomed at Glendale High School, where Feeney was working at the time of the slayings.

``There will be no classroom discussion and there will be no viewing of TV, not a 30 seconds worth,'' Principal Barbara Buffington said. ``That situation has impacted us as much as it's going to.''