KEY POINTS:
Schoolgirl kidnapper Philip Foss was caught through the forward thinking of a constable who collected a voluntary DNA sample from him more than a year before the crime was committed.
Foss, who was this week sentenced to three years and three months in prison, was arrested after scientists matched his DNA to a semen sample found in his car.
The semen was on a tiger pattern blanket the 14-year-old victim pulled from her attacker's moving car as she escaped through a back door.
Detective Sergeant Glenn Baldwin said the semen sample matched a DNA sample Foss had given police nearly a year earlier.
Foss had previous convictions, but the sample was not believed to have related to any of them.
A female constable, who was talking to him about another matter, had thought it might be wise to have his DNA on file and he agreed to give a sample.
Mr Baldwin said more and more criminals were being caught through voluntary DNA samples they had given police.
"It really is the fingerprints of the new millennium," he said.
But as the success rate increased people were becoming more wary about giving samples, knowing it might one day lead to their arrest.
Mr Baldwin said that in the Foss kidnapping, the DNA helped clinch the case for police, but it was just one of several tools they used during the investigation.
Officers worked extremely long hours, fearing that if they didn't catch the offender he would try to pluck another schoolgirl off the street.
Foss, then aged 25, had spent the night before last year's kidnapping drinking heavily with friends at various places, including a brothel.
He had been under the influence of cannabis and when he arrived home drunk, his partner told him to go somewhere and sober up.
"That just seems to have triggered in you not a sense that it was time to slow down but a sense that you wanted to keep the party going," said Judge Lindsay Moore on Wednesday.
Instead of sobering up, Foss tried to snatch a 17-year-old schoolgirl off the road as she walked to school on a Friday morning.
He approached her, told her he wanted her to get into his car. When she started yelling he pointed to an object covered by a black T-shirt at her chest.
The girl thought it was a gun. She tried to get away and Foss grabbed at her, but she eluded him and he drove away in his car.
He returned to the same spot two hours later.
This time he targeted a 14-year-old girl. When she screamed, he covered her mouth with his hand, picked her up and carried her to his car.
She managed to sound the horn - which drew the attention of some nearby construction workers - but Foss started the car and drove off.
Terrified, the girl climbed into the back seat, and as Foss slowed the car at an intersection she opened the door and rolled out on to the road, dragging a large blanket from the back seat with her.
It was that stained blanket that eventually led police to Foss.
