When Steven Greenwood flicked his smoked cigarette onto the footpath outside his Victorian home in September 2012, he unwittingly linked himself to a brutal rape scene 28 years in the past.
The butt gave police the crucial DNA evidence they needed to charge Greenwood with raping a woman at knifepoint in her Melbourne bedroom in 1984.
Detectives watched him smoke his cigarette from their car outside his Shepparton residence and pounced when he discarded it, a Victorian County Court judge said on Monday.
Forensic testing matched DNA from the butt to a pillowcase found at the crime scene and Greenwood was arrested in December 2012.
The nurse and born-again Christian later pleaded guilty to rape, indecent assault, burglary and theft stemming from the attack on the sleeping woman. Jailing Greenwood, Justice Gabriele Cannon said he broke into his victim's Kew home about 2.30am on November 15, 1984, bound her and repeatedly raped her.
The near 30-year mystery surrounding the identity of her attacker had left the woman in constant fear and set back her once-promising career, Justice Cannon said.
Police interviewed Greenwood, 59, in 1984 and 1993 and both times he denied the attack. They reopened the case when a new taskforce was set up in 2008 after advances in DNA testing. Justice Cannon sentenced Greenwood to eight years in jail, with a minimum term of six years.