A former North Sea driller whose twisted dad murdered his mum and sister yesterday backed Scotland’s new coercive control law.

Luke Hart, 29, had returned to Aberdeen, where he was working, the day police contacted him about the horrific killing.

His father Lance had shot his wife Claire and their daughter Charlotte, 19, before turning the shotgun on himself.

The bloodbath in Moulton, near Spalding, Lincolnshire, happened after Luke and brother Ryan thought they’d prised their mum from his controlling clutches.

The siblings wrote a book about their upbringing and events that led their dad to snap in a swimming pool carpark in the summer of 2016.

It wasn’t until after their father, hiding under a car, had ambushed and killed their family that they first heard about coercive control.

Now Luke is backing campaigners in Scotland spreading the message that domestic abuse isn’t only physical but mental torture, too.

Lance Hart who murdered his wife Claire and daughter Charlotte

Before addressing Grampian Women’s Aid’s first ever conference on domestic abuse, Luke spoke to the Daily Record.

He said: “It took us a while to understand what had happened to our family.

“Our father had been coercively controlling but hadn’t been violent.

“We’d never seen the coercive control, so it took us a year to understand the behaviour patterns that led to the murders of my mum and sister.”

Luke, who now works for a major oil company in London, said: “As a child, you look to your parents to learn the rules, to learn about reality and learn about life.

“Coercive control in particular is about power and control, it’s domination.

“The perpetrator creates a system of rules at home which are claustrophobic.

“As a child, you just take those rules as given and try your best to adapt to them.

“So – outside our home – we looked incredibly disciplined, self-sacrificing, really determined children because we’d learned we couldn’t ever make mistakes.

“We had to do everything right first time otherwise our father would be incredibly aggressive towards us.”

Charlotte Hart was shot dead with her mother Claire Hart

Ticking timebomb Lance never hit his children but used mind games to exert cruel control over his family.

Luke said: “What we found out – unfortunately, after the murders – was our father had been very controlling when he first met mum.

“He’d flattered her and seemed nice but he quickly moved the relationship to where mum was past the point of no return.

“He said to her, ‘Let’s move away from your friends and family to live the countryside where it will be idyllic’.

“She refused, so he fed me a peanut at age three. I was allergic to nuts and was rushed to hospital to save my life.

“But he used that as a threat that if mum didn’t obey him, then us children were at risk.” Lance had a low-paid job in a builders’ yard but would stay at home and keep close tabs on his family.

After moving them into the Cambridgeshire countryside, the family were self-sufficient and the children only left to go to school.

Their income was so low, Luke and Ryan got Government grants to go to university and eventually secured well-paid oil jobs.

Luke Hart backs Scotland's new coercive control laws

Sending money home from Scotland, the boys hoped Claire would be able to leave but their dad kept the hand-outs for himself.

Eventually, their mum and sister walked out when the boys got them rented accommodation in a nearby village.

The family never believed their father would kill but removing his control drove him over the edge.

Luke said: “We didn’t know he was dangerous. If we had, we’d have gone invisible.

“Mum had her job and new friends and we moved her to a nearby town but he knew her routine.

“Five days after we’d moved them out, he met them and that was when he killed them.”

Luke is convinced his father deliberately killed Charlotte first in front of her mum

He said: “That was the same threat that had hung over my mother from the beginning – the children are at risk if you don’t obey me.”

Coercion includes isolating a partner, financial control, spying on them and dominating their lives.

The new act outlawed the behaviour in April and up to June 414 crimes were recorded and 13 people convicted.

Scottish Women’s Aid chief executive Dr Marsha Scott said: “Coercive control stayed in the ‘too hard’ box but this law allows the police to gather evidence and fiscal to prosecute using information about the family, the relationship and offending behaviour we’ve never been able to bring into a courtroom before.

“It is now against the law, it’s out of the box and the proof will be in the pudding. Do we make it work the way it was intended to work?”