VIDEO: Man details how he killed Fairfax County mother in confession video 29 years later

FAIRFAX COUNTY, Va. ( DC News Now ) — A chilling confession video is now public after a man pleaded guilty to killing a mother in Fairfax County more than two decades ago.

Investigators used DNA evidence to connect software engineer 53-year-old Stephan Smerk to the murder of 27-year-old Robin Lawrence 29 years later, ending in a guilty plea earlier this month.

Smerk had been working as a software engineer and living with his wife in upstate New York at the time of his arrest in September of 2023.

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He was in Lawrence's neighborhood with friends before he entered Lawrence's home on Nov. 18, 1994, the evening of the killing. He admitted to investigators that he'd been drinking and taking pills. He said he felt he "needed to kill someone."

He and Lawrence did not know each other when he killed her – he was stationed in Arlington with the Army at the time.

Portions of his confession were read aloud during his guilty plea hearing on Oct. 4. Family members said afterward that Smerk appeared to have no soul.

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In his confession, he described entering her home and walking past Smerk's 2-year-old daughter's room. He cut her phone line and stabbed the woman, leaving her toddler daughter unharmed.

"I cut her up real good," Smerk told investigators. Lawrence was stabbed 49 times.

As part of his plea deal, Smerk will serve no more than 70 years in jail and will be eligible for parole.

His sentencing is scheduled for March 2025.