Murderer who tried to kill fellow inmates in Yorkshire prisons has minimum term extended
Duncan Heaton, 53, has had another 13 years added to his sentence
Last updated 12th May 2026
A convicted murderer who tried to kill two fellow inmates in different top security prisons has had another 13 years added to the minimum term he must serve until he is considered for release.
Duncan Heaton, 53, was already serving a life sentence with a minimum term of more than 21 years for the murder of a man in Hull when he attacked sex offender Andong Abong Ashu with a knife at HMP Full Sutton, near York, in May 2024, Leeds Crown Court heard on Tuesday.
Heaton was then moved to HMP Wakefield, where he tried to kill fellow murderer David Minto in October last year with makeshift weapons.
Mr Justice Cotter said he was satisfied that the motivation for the attacks was because the victims were sex offenders, telling the defendant he appeared to have a “warped and misconceived belief in your moral superiority”.
Heaton, who appeared by video link from the segregation unit at Wakefield, was told by the judge: “While serving a life sentence for murder, you committed two further offences of attempted murder within 17 months.
“Both of which were premeditated and planned attempts to stab fellow inmates to death, motivated by the fact that they were sex offenders.
“You appear to have some warped and misconceived belief in your moral superiority over some other prisoners.”
The judge said: “You are an exceptionally dangerous man and I have little doubt that you would consider attacking another prisoner who had been convicted of sexual offences in the future if the opportunity arose.”
Heaton’s barrister David Godfrey said his client wanted a whole-life tariff to be imposed, so he would never be released from prison.
But the judge said these offences, despite being very serious, did not warrant a whole-life tariff “leaving no hope of release”.
He told Heaton: “You have expressed a desire to remain in custody for the rest of your life. You believe that you are dangerous.”
The judge imposed a further life sentence with a minimum term of 13 years, which will be added to his original tariff.
Heaton was already serving life with a minimum of 21 years and six months for the murder of Keith Opray in Hull in 2014.
The judge said Heaton had already served 11 years and 10 months of the original sentence.
The judge said the defendant will be in his 70s before he can be considered for release, and added: “Whether you are ever safe to be released, well that will be a matter for the Parole Board.”