A wife and husband killed themselves as a police rape investigation closed in on him, an inquest heard.
Downes had been jailed for attacking prostitutes
Christine Downes, 51, drove with her husband Christopher, 54, to a chalk pit near Andover, Hampshire, last October and gassed themselves in a car.
Downes had just provided a DNA swab for police investigating two rapes and an aggravated burglary in Salisbury in 1984 and 1985, the inquest heard.
Two verdicts of suicide were recorded by the coroner.
The inquest in Winchester heard from Det Insp Sean Memory that Downes - who had previous convictions for attacking prostitutes - had been on the periphery of the investigation in the 1980s.
When the case was revisited in 2006 and featured on Crimewatch, his name came up again.
He initially refused to give a DNA sample.
The hearing was told that the pair wrote letters to their family explaining why they were going to kill themselves on the same day Downes eventually gave a sample, which matched a semen stain found at a rape scene in 1984.
When police broke into their home after they were found dead from carbon monoxide poisoning, they found the letters and a list of songs they wanted played at their funeral.
Mr Memory added that there was nothing to link Downes to the aggravated burglary but he said: "Had he been alive he would have charged with a series of offences and faced trial."
Mrs Downes had stood by her husband when he was jailed for four years in 1990 for an attack on a prostitute in Southampton.
In 1987, he also served six months for attacking a prostitute in the same city.
Central Hampshire coroner Grahame Short said: "They deliberately planned to kill themselves.
"There is no doubt that Christopher Downes would have been charged with these serious offences. He feared that would be precisely what was going to happen."