The death of a prison inmate who was found with a bag and belt around his head has led to changes in prison healthcare.

James Duggan – whose family yesterday paid tribute to a “beautiful boy” – was 27 when he was found in his cell in HMP Pentonville on August 4, 2010, before being rusticated. He was pronounces dead at the Whittington Hospital two days later.

Yesterday a jury at St Pancras Coroner’s Court recorded a narrative verdict, unanimously ruling that despite rules being followed, intervention was needed after he deteriorated mentally and became psychotic.

The verdict ruled there was no way of establishing whether any of his “fears” or allegations he made in a phone call to his father – including thinking prison officers were fuelling rumours he was a paedophile and a nonce – were “psychotic or based on reality.”

But the court had earlier heard from a psychiatrist who suggested he could have been hearing voices in his head and was not bullied by anyone.

The verdict also stated that an Assessment, Care in Custody and Teamwork (ACCT) file, which would have stepped up care monitoring, should have been initiated following signs of self-harm, and that the bag and belt he used should have been removed.

The jury foreman told the court: “James Duggan’s behaviour appeared to have changed dramatically whilst on the segregation unit, without proper mental health assessment there was no way of establishing whether his fears were psychotic or based on reality.

“Also, in light of the evidence given by the pathologist, regarding the marks [lacerations], we believe an ACCT should have been opened on August 3.

“Although an ACCT would not have increased the number of observations, it would have drawn attention to Mr Duggan’s perceived mental health issues and increased interaction between Mr Duggan, prison officers and health care staff.

“His bag of possessions should have been removed from his cell and Mr Duggan should have been searched prior to being placed in his cell on the health care unit.

“We unanimously agree that adherence to correct policy and procedures contributed to Mr Duggan’s death.”

As a result, prison healthcare has now been reformed.

In a moving tribute Mr Duggan’s family, who attended court, along with his sister, Jodie, who gave evidence, said: “James was a beautiful boy whose smile was as big as his heart.

“He will be missed always by his family and friends who loved him very much. We just hope James can rest in peace now.”

The 27-year-old, of Wharf Road, who had been on remand in HMP Pentonville awaiting trial over an alleged assault, died of starvation of oxygen to the brain caused by asphyxiation of the plastic bag.

Whittington Health, Camden and Islington NHS Foundation Trust and Barnet, Enfield and Haringey Mental Health Trust, who provide healthcare at Pentonville, said: “We have reviewed the care given to Mr Duggan and have since implemented all the subsequent recommendations in relation to healthcare at Pentonville prison to protect patients who are at risk of suicide or self-harm.”