Cult leader Mark Christopher concludes his speeches and everyone is cheering. The charismatic teacher has finished another day of online lessons. Yet lurking behind the smiling face are sinister intentions to radicalise, incriminate and profit from his willing students. How did he end up persuading his followers to storm a court and attempt to kidnap a senior coroner?

Lincoln Brookes was driving to work on 20 April 2023 when he took a panicked call from his colleague.

“Those people who are in that letter… they are coming to get you,” he was told by area coroner Michelle Brown.

Mr Brookes was arriving at Essex Coroner’s Court later than usual that day due to a pressing family matter.

Had he turned up on time, the widely-respected senior coroner would have been handcuffed, bundled into a car and kidnapped from Chelmsford.

Only Mark Christopher, 59, Sean Harper, 45, Shiza Harper, 38, and Matthew Martin, 47, know what would have happened to him next.

They were all found guilty at Chelmsford Crown Court of conspiracy to kidnap and conspiracy to commit false imprisonment in July.

On Monday, Christopher was jailed for seven years and the other defendants imprisoned for 30 months.

It was a plot masterminded by Christopher, the so-called chief judge of an online anti-establishment movement called the Federal Postal Court.

“My jurisdiction runs over any language within governments, courts and corporations,” the 59-year-old states on his website.

Gaining his wisdom comes at a cost though. For £7,449, students can take part in his eight-part online university course that teaches people how to clear debts, win legal redress and pay their taxes.

But the highlight of the webinars is the insight into what Singapore-born Christopher preaches to be the hidden meanings of words used in everyday language.

Normal words such as person, nice and even smart meter all have covert, sinister meanings, the cult leader tells his followers.

Christopher, from east London, believes these so-called secret inferences are bringing harm to people across the world.

Dr Alexandra Stein, a social psychologist and author who specialises in cults and totalitarianism, says it is typical “cult-speak”.

“You can go and read their belief system, it’ll drive you crazy,” she says.

“He’s just, as many cult leaders do, picked from here and there, making up ideologies and systems.

“If you were really wanting to get some information you would stay hooked on, waiting for this gobbledegook to be over to get it.

“You concentrate and you try to make sense of something that’s essentially nonsense and, actually, that’s part of getting you hooked further in.”

In letters written to Mr Brookes, Christopher accuses him of being a “detrimental necromancer” and says the coronial process is illegal as “you can’t be dead on paper”.

Other accusations include Essex Coroner’s Court “interfering with the dead” and warning Mr Brookes he would be subjected to corporal punishment.

Such are Christopher’s beliefs that he has legal powers, he uses a picture on his website of him wearing a suit claiming to be a judge.

It was these delusions that saw Christopher rally members of the Federal Postal Court to attend Seax House, Chelmsford, in April 2023.

Wearing hi-vis jackets while holding handcuffs and placards, Christopher, Martin, and Sean Harper and his wife Shiza stormed into courtroom two in search of Mr Brookes.

The defendants wanted to abduct him from his place of work over “fraudulent activity” they believed he was committing.

They instead found Mr Brookes’ colleague, Michelle Brown, in the middle of an inquest. They demanded she summon him.

A fracas ensued and the group eventually left, with Martin arrested in Chelmsford and the three others later detained by police in Southend-on-Sea.

But why target a coroner who works to give families closure after the death of a loved one and highlight failures by organisations?

“Cults have to keep their members busy, they have to keep them engaged in things,” Dr Stein says.

“Otherwise, they’re going to have time to think and reflect, and a cult leader doesn’t want that because they might then realise it’s all nonsense and leave.”

Dr Stein says cults, including the Federal Postal Court, attempt to isolate members from their loved ones.

Among the various courses on Christopher’s website is one which teaches people how to “overcome and destroy the devastating effects of narcissists and psychopaths” at a cost of £280.

This is a technique employed by cults to ensure members do not heed advice from family and friends to leave the group behind, according to Dr Stein.

“It’s absolutely textbook. In fact, they have to do that for this machine that is cultic brainwashing to work,” she says.

“If you isolate people and make the outside world seem to be wicked and bad and damaging, they’ve got nowhere else to turn other than the group and that locks them in.”

Giving evidence during the trial, Martin tearfully defended the cult leader who he said had “saved” him from bad influences in his life.

He said Christopher had allowed him to take part in the £7,449 online university course for just £1.

It meant 6ft 5in (1.98m) tall Martin was qualified in time to act as Christopher’s bodyguard when they stormed the court in Chelmsford on an April morning.

The Harpers, from South Benfleet, Essex, described how Christopher had taught them things they never would have known without his lessons.

They all denied the prosecution’s allegation that they were members of an “anti-establishment cult”.

Instead, Christopher was their teacher and they went to the court with him to “stop the fraud”.

But Det Ch Insp Nathan Hutchinson, of Essex Police, says Christopher is a “radicaliser” who targeted and recruited them.

“He’s a very outgoing individual, he has definitely got a lot of charisma about him,” he says.

“He’s very good at manipulating people – people with debts, people with problems have come to him; they’ve signed up to his online courses and believed everything he was doing was legal.

“He’s recruited people, normally unknown to him, and that has resulted in them committing a very serious criminal offence.”

Appearing in court, the group were disruptive. At times they heckled Mr Justice Goss, directly appealed to the jury from the dock and shouted over evidence.

But Christopher remained silent throughout. The cult leader was such a serious concern to police that he was remanded in custody from the point of his arrest.

The withdrawn figure who appeared in the dock was a far cry from being “one of the greatest teachers of our generation”, as he is described by a follower writing his book.

It also did not mirror the supposed bravery of a man who claims to have reversed a terminal disease in 14 days earlier in his life.

Det Ch Insp Hutchinson says the case is like nothing ever seen in the UK courts before.

“It was a very brazen incident and it did send shockwaves through the coroner’s court staff and the wider judiciary community within Essex,” he says.

“We’re very lucky in this case the coroner wasn’t there.”

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