Last month, Niagara County Judge Sara Sheldon refused to let defense attorneys offer an alternative killer theory in the 1993 death of 17-year-old Mandy Steingasser of North Tonawanda.
Monday, Sheldon changed her mind.
The turnabout comes one week before the start of jury selection in the trial of Joseph H. Belstadt, 44, of the Town of Tonawanda.
He was charged almost two years ago with murdering Steingasser, after DNA testing concluded that two of Steingasser's hairs were in his car when police seized it in 1993.
The defense team will be allowed to try to incriminate Steingasser's ex-boyfriend in the young woman's death.
Previously, the judge had ruled that forensic findings of the ex-boyfriend's DNA in Steingasser's underwear weren't a good enough reason to allow the defense tactic.
Two developments led Sheldon to change her ruling.
One is a sworn statement North Tonawanda police recently obtained from the ex-boyfriend, who now lives in Florida.
"It is rife with inconsistencies, not only pertaining to his whereabouts but to how his DNA got into Mandy Steingasser's underwear," defense attorney Michele G. Bergevin said in court.
The other factor is the addition of Tammy Belstadt, the defendant's half-sister, to the prosecution list of 86 witnesses.
Bergevin said Tammy Belstadt told her that she saw the ex-boyfriend skateboarding on the steps of a church after a party that Steingasser attended on the night of Sept. 18, 1993.
That's the night Steingasser was last seen alive and a night after the boyfriend was supposed to have left North Tonawanda for Florida, according to previous arguments from District Attorney Caroline A. Wojtaszek.
Bergevin contended he left the day of the disappearance.
Wojtaszek said the existence of the boyfriend's DNA in Steingasser's underwear doesn't prove when it got there.
"You have a person who may have been in North Tonawanda, although the evidence suggests otherwise," Wojtaszek told Sheldon on Monday.
Previously, Wojtaszek said she could present witnesses to prove the boyfriend was out of town.
The judge also will allow testimony by Karrie Belstadt, the defendant's first wife, that while they were dating, Joseph Belstadt told her that he gave Steingasser a ride in his car on the night in question.
Defense co-counsel Mark Murphy argued other witnesses will say the same, so the testimony is unnecessary.
Monday, Wojtaszek said that Joseph Belstadt told police he dropped Steingasser off at a church at First Avenue and Oliver Street, where a man was waiting. The description the defendant gave for that man looked nothing like the boyfriend, Wojtaszek said.
Even though it's not a rape case, Sheldon said the rape shield law will apply, meaning that Steingasser's sexual history is out of bounds in the trial.
Her body was found Oct. 25, 1993, in Bond Lake County Park in Lewiston, with her bra around her neck.
A coroner's report ruled the death was caused by strangulation. Though Bergevin objected, Sheldon will let the prosecution present evidence about how long it takes to strangle someone to death with a "ligature"; in this case, a bra.