We take a look back at the case.
Robert Wilson, who changed his name to Joshua The High Priest by deed poll, was jailed for 17 years in 2009 after a cold case team from South Yorkshire Police began reviewing unsolved sex crimes carried out across the county.
In the first incident, in October 1984, Priest, now aged 66, and originally from Broomhall, posed as a taxi driver and picked up an 18-year-old bar worker as she left work after a shift at a nightclub.
In the second incident, in June 1985, Priest broke into a flat in Broomhall and subjected a 17-year-old girl to a horrific sexual attack at knifepoint.
He was arrested at the time for the second attack but was never charged because of insufficient evidence.
At his trial in 2009, Sheffield Crown Court heard Priest’s first victim got into his car after he tricked her into thinking he was a cab driver.
She gave him directions to her home but he drove the opposite way, stopped at a car park in Broomhall and raped her in the back of the car before dropping her off near Bramall Lane.
The rape was reported to the police but the court was told the girl didn’t want to continue with the police investigation.
Following Priest’s attack, the girl became so distressed she twice attempted suicide.
The second attack happened eight months later when Priest broke into a flat in Broomhall along with an accomplice, and woke a 17-year-old sixth form student who was staying with her boyfriend.
Priest armed himself with an ornamental dagger, which was hanging on the wall and demanded money.
After her boyfriend had handed over his £150 coin collection, Priest took the girl down to the kitchen, swapped the dagger for a bread knife, then pinned her down and sexually assaulted her.
During his trial at Sheffield Crown Court in 2009 the jury heard Priest had a string of previous convictions for sexual offences. He had been jailed for seven years in 1986 for raping and robbing a prostitute in Sheffield just weeks after the attack on the student.
He was also jailed in 1993 for three years for the indecent assault of a 10-year-old girl.
Sarah Wright, who is now a judge at the court, defended Priest during his trial. She said he had his own business and had brought up his children alone after their mother left home.
But, sentencing him, Judge Graham Robinson said Priest had shown no remorse for his crimes.
South Yorkshire Police’s cold case review team was set up to review the most serious unsolved murders and rapes in the force area. They began to investigate the attacks carried out by Priest in 2007.
They used advances in scientific technology, such as DNA profiling which didn’t exist when Priest struck, and re-examined forensic evidence recovered from the crime scenes. They were able to establish that the same man had been responsible for the attacks on both women.
When the officers checked the national DNA database they discovered the profiles recovered from the crime scene evidence in the 1980s matched that of Priest.
There was a one-in-a billion chance and a one-in 900 million chance the profiles obtained were from other people.
At the time of Priest’s conviction, Scientist Mike Wilson said: "DNA profiling technologies have advanced rapidly since the 1980s which allows us to re-examine materials retained from the original investigation.
"Low Copy Number DNA is our most sensitive DNA technique which can yield results from very small samples of DNA as well as old and degraded materials."
The cold case team was disbanded in 2014 but was made up of retired detectives who were re-employed as civilian investigators. They enjoyed considerable success, putting 12 men, who thought they’d got away with their crimes, behind bars.