John Heinzelman

Heinzelman said the test of Ian Mitchum's retained blood sample was a full match to the PMH stain and all scene DNA.

“This is a 100% match to our PMH, to all the DNA in the scene”

20/20: Home Alone (Oct 3, 2026) · Listen from 52:27

Heinzelman described the PMH stain on the dining room floor as the item that stood out from everything else at the scene.

“It was the sore thumb that sticks out amongst everything else”

20/20: Home Alone (Oct 3, 2026) · Listen from 24:26

Heinzelman characterized the defense's focus on the pharmacist as the familiar 'some other dude did it' strategy.

“The defense always has this, what we call the Saudi defense. Some other dude did it”

20/20: Home Alone (Oct 3, 2026) · Listen from 1:16:32

Heinzelman called Arizona's first use of familial DNA in the Feldman case groundbreaking.

“Allison's case is the very first case in Arizona where familial DNA was used”

20/20: Home Alone (Oct 3, 2026) · Listen from 47:59

Heinzelman said the lack of a CODIS hit indicated the killer had never been arrested and was not in the system.

“It tells us that this person has never been arrested, that this person is not in the system”

20/20: Home Alone (Oct 3, 2026) · Listen from 26:46

Heinzelman said a witness's report of a scream put the murder around 9:30 p.m., and door records showed the killer left at 1:04 a.m.

“Based on a witness that heard a scream sometime around 9.30, that Tuesday evening is when I believe the murder occurred”

20/20: Home Alone (Oct 3, 2026) · Listen from 15:24