Jesse Western, 17, suffered a fractured skull and a brain haemorrhage when he stepped out in front of a lorry days after being detained under the Mental Health Act.

The teenager survived the incident but was left with serious injuries from which he is still recovering.

But his family say the life-altering incident could have been avoided if his autism spectrum disorder had been correctly managed by the Norfolk and Suffolk NHS Foundation Trust (NSFT).

And Stuart Richardson, chief executive of NSFT, has apologised in writing to Jesse and his mother, Stella Owens, for the shortcomings in his care.

Michael Portman-Hann, of the family's legal representatives FBC Mandy Bowdler, who is pursuing a clinical negligence claim on their behalf, said Lauren Coates, a consultant psychiatrist, had originally dismissed his condition as being as a result of Ms Owens' parenting.

He said: "The doctor in the children and young people's mental health team decided at Jesse's first appointment in 2015 that although he had autistic traits, the behaviours Jesse was showing were because of his mother's parenting.

"As a result, she refused to give Jesse the diagnosis of autism spectrum disorder (ASD) which would have meant a treatment plan was put in place for him.

"To compound the damage, the consultant also refused to accept the diagnosis of a later private assessment that found Jesse did indeed have ASD."

He added that five years later, in June 2020, when Jesse was admitted to the Queen Elizabeth Hospital, King's Lynn, under the Mental Health Act, Dr Coates "refused" to do a full assessment on him.

He was discharged and three days later attempted to take his own life.

Mr Portman-Hann added: "This was a catalogue of decisions made on the basis of personal prejudice against Jesse's mother and not on the clinical needs of Jesse himself."

Ms Owens said: "When Jesse had his first appointment in 2015, the consultant fixed on me and my parenting, saying Jesse's behaviour was his way of getting his needs met.

"She couldn't - or wouldn't - get past that.

"Had she made an ASD diagnosis at that point, we would have had a treatment plan and some tools to prevent Jesse's anxiety reaching crisis point.

"None of this should have happened and Jesse should never have got to the point where he felt he had no other way out.

"As a result of the trust's failures, Jesse has lost out on so many opportunities which could have been awarded to him had he received an earlier diagnosis.

"This has had a substantial effect on his education and Jesse feels he has missed out on being able to enjoy his formative years."

In a letter to the family, Mr Richardson wrote: "I offer my sincere apologies for the trust's failures to appropriately manage Jesse's autism spectrum disorder and undertake a comprehensive psychiatric assessment following his admission to the hospital.

"I was desperately saddened to hear that had a psychiatric assessment occurred prior to his discharge home, this is likely to have avoided Jesse's attempt to take his own life.

"I am truly sorry that the trust failed you both and for the impact this has had on you and your wider family.

"The trust always strives to provide the highest quality of care to its patients and I can assure you that the failings identified in care on this occasion have been shared with all practitioners and agencies involved with the intention of learning and ensuring no-one else should suffer this experience."