A 90-year-old man who physically and sexually abused boys in his care at a residential school in the 1960s has branded his victims “unhinged” and said they should be investigated by police for “telling lies”.

Michael Murphy appeared by video link at the Scottish Child Abuse Inquiry on Wednesday from HMP Edinburgh, where he is serving a sentence for physically and sexually abusing children while he was a social worker with the De La Salle Brothers in Gartmore, Stirlingshire, and St Joseph’s in Tranent, East Lothian, between 1961 and 1991.

Murphy continued to deny he was responsible for abusing boys in his care while he was working at the establishment, and described those who had brought allegations, resulting in convictions in 2003, 2016 and 2021, as “characters” who were motivated to complain for “financial gain”.

The former monk became a member of the De La Salle brothers in 1956 and was posted to St Ninian’s School in Gartmore in 1961.

Murphy was asked by lead counsel to the inquiry, Colin MacAulay KC, how he felt about the allegations.

Murphy said: “All of these characters and complainers, they are unhinged … and I think they need to be checked out by the police and need to be investigated about all of these lies they have told.”

During Wednesday’s evidence, the inquiry heard Murphy had been convicted of 54 charges of physical and sexual abuse, including incidents where he would hit boys on the bottom with an implement made of three 16in shoe laces if they were misbehaving, and that he administered electric shocks to boys using a small generator he called “the tickler”.

The inquiry also heard about an incident where Murphy assaulted a boy so badly, he broke his arm and had to be taken to hospital.

Murphy downplayed the incident and attempted to place blame on the child, saying the youngster had “abused” him because of his “footwear” and described it as a “misunderstanding”.

He said: “I had a misunderstanding with a boy about my footwear and my bad foot.

“I gave him an arm twist. I twisted his arm.

“That’s all.”

Lead counsel to the inquiry Colin MacAulay KC put it to Murphy that the child sustained a broken arm as a consequence.

Murphy said: “He fractured a wee bone on his arm.”

He was later asked about administering electric shocks to children, with one incident causing burns to a boy’s hand.

Murphy continued to insist he was not administering shocks and said the sensation went along the muscle of the hands and that the complainer was “telling lies”.

Mr MacAulay asked Murphy if he had ever administered a shock through the testicles.

Murphy denied he had and said his convictions were “false”.

He said he had been entrusted with the care of around 90 children on his own, with very little training in how to look after them.

When asked to explain why so many people came forward regarding Murphy’s treatment of the children, he said there had been “collusion”.

Mr MacAulay asked Murphy: “Why are they picking on you?”

Murphy responded: “I have already said it is because I am the only one alive today.

“It is all about compensation.”

Meanwhile, the inquiry also heard from a teacher at St Joseph’s between 1978 and 1994, known simply as William, who was accused of hitting boys with blackboard dusters and making them sniff ammonia as forms of discipline.

William told the inquiry he used blackboard dusters to tackle “classroom nonsense” and said the boys would often throw the dusters back at him.

He insisted he did not use physical punishment and witnessed it at the school only once when a boy had taken off the handbrake on a minibus.

When asked about boys being made to smell ammonia, he said he had been talking about “smelling salts” and told the boys he could let them smell ammonia.

He said the accusations of abuse towards the boys were “upsetting” because he believed he had “always got on well” with them and had spent much of his career working with children who had social, behavioural and emotional difficulties.

William has not been convicted of any offences related to the allegations.

Later on Wednesday, a social worker denied accusations of abuse against him when he worked in residential care and said no behaviour he would categorise as abuse took place.

No criminal complaints have been made against the man, who gave evidence to the inquiry under the pseudonym Dominic.

He worked at institutions run by the De La Salle brothers during the 1980s.

Dominic had been accused of hitting boys and looking at them inappropriately while they were changing.

He strenuously denied the accusations put to him at the inquiry.

He said he had never witnessed any physical punishment towards the children in his care, and he described St Joseph’s as a “remarkable” place that was “quite progressive” with an approach that would be described as “restorative” nowadays.

Dominic also discussed Murphy’s electric generator and the sensation it gave as “underwhelming”.

He was asked by Mr MacAulay if he had ever seen any abuse at St Joseph’s during his time there.

He said: “I honestly did not think I saw behaviour with any kid that I would consider to be abusive.”

In 2017, the De La Salle Brothers used the Scottish Child Abuse Inquiry to apologise to victims who had suffered abuse within their care.

The spokesman for the De La Salle Brothers, David Anderson, said nothing could be said to defend the mistreatment of children.

“Where a brother at any of these schools was responsible for the mistreatment of a child or young adult entrusted to the congregation’s care, the congregation offers an unreserved apology,” he said at the time.

The inquiry, before Lady Smith, continues.