NIAGARA FALLS, N.Y. (WIVB) — On Friday, the jury in the Joseph Belstadt trial heard testimony about the DNA evidence that led to Belstadt’s arrest in 2018.

Belstadt is accused of killing 17-year-old Mandy Steingasser in 1993.

The testimony about the DNA has been anticipated since it was mentioned in both lawyers’ opening statements nearly two weeks ago.

Retired Niagara County Sheriff’s Office forensic chemist Mark Henderson testified about his 1993 examination of hairs and fibers vacuumed from Belstadt’s car, which he reexamined in 2017.

Henderson testified he took evidence from Steingasser’s autopsy and received vacuumings from Belstadt’s car back in 1993.

He said in 2017, he reexamined a pubic hair of Steingasser’s taken from the autopsy and two hairs from the vacuumings from the passenger’s side rear seat of the car.

He said he found both hairs from the car to be pubic hairs with characteristics consistent with Steingasser’s pubic hair.

He also testified the root of the hair indicated force was used to remove it.

Henderson also testified about two fibers taken from bags that held the underwear and jean jacket found on Steingasser’s body.

He said he compared these fibers with a fiber collected in 1993 from the passenger’s side backseat carpet floor of Belstadt’s car.

Henderson said the fibers were similar and he couldn’t find any differences between the known samples and the ones from Steingasser’s clothing.

On cross-examination, Belstadt’s attorney tried to discredit Henderson’s expertise in hair analysis.

Kayla Green is a reporter who has been part of the News 4 team since 2021. See more of her work here.