An aristocrat’s son took his own life after a mental health team failed to give him proper care in the days before his death, a coroner has ruled.

Essex University student Rupert Green, 21, who is the son of Lord Nicholas Monson, died in January 2017, five days after he hanged himself in his mother’s garden in Surrey.

He was suffering psychosis which his family believe was triggered by skunk cannabis.

Coroner Anna Crawford said the mental health trust failed to refer him to a special service which could have watched him more closely before his death.

Rupert was refused an assessment by Surrey and Borders NHS Trust’s home treatment team three days before he hanged himself.

A nurse rejected the referral, made by the Safe Haven mental health centre, despite Rupert’s claim there would be “blood” on his mother’s hands if people did not believe he was the son of God.

His mother Karen Green had texted a mental health nurse the day her son took his life asking for help but got no reply.

Lord Monson’s first son, Rupert’s half-brother Alexander Monson, 28, also died tragically, allegedly killed in police custody in Kenya.

Lord Monson launched a “war against skunk” after his son’s suicide, urging Government to decriminalise weaker strains of cannabis to prevent abuse of stronger strains.

Ms Crawford said there was a failure on the part of the home treatment team to accept the referral but she did not say the failure caused Rupert’s suicide.

Addressing Karen Green, after giving the conclusion of suicide, she added: “You did everything within your power to seek help for your son, which you so clearly knew he needed.”

The inquest heard Rupert’s life had “appeared to be proceeding smoothly” until his family spotted problems in the Easter holiday of 2016.

He claimed roommates at the university, where he studied biology, were spying on him.

Mrs Green said: “He told me the girls in the shared house he had in Colchester were hacking his computer and spying on him.”

Mrs Green told the inquest: “Before Christmas 2016 Rupert asked to be readmitted to hospital. The nurses told me he would not fit the criteria so he would not be admitted.”

In the days before his death he reported hearing voices.

Mrs Green said: “He said he was the son of God, people made the sign of the cross when he walked by and called him shepherd.”