A 55-year-old man who collapsed during a police raid and later died of a cardiac event had no marks on his body to suggest he had been restrained excessively, an inquest jury has heard.
Cyril McGuinness organised and supervised the kidnap and attack on Fermanagh businessman Kevin Lunney.
The Quinn Industrial Holdings director had his leg broken, was doused in bleach and the letters QIH were carved into his chest before he was dumped on a roadside in Co Cavan.
Chesterfield Coroner's Court was told McGuinness woke in bed at his home in Buxton, Derbyshire, to find himself surrounded by police officers wearing stab-proof vests, during a search requested by the Police Service of Northern Ireland.
The first day of an inquest before a jury of three men and eight women was told Derbyshire Police forced their way into the property while exercising a warrant on November 8 2019, and that towards the end of their search operation Mr McGuinness went into cardiac arrest.
The inquest was told the warrant was linked to "serious matters" in Northern Ireland for which others stood trial.
Forensic pathologist Guy Rutty, the first witness at the hearing, said he had conducted a post mortem after being informed that Mr McGuinness, who had significant pre-existing coronary disease, had been placed in handcuffs and was "fully compliant" during the raid.
Professor Rutty said Mr McGuinness had been given a nicotine patch by police after requesting one, as well as being allowed to have a cigarette.
The pathologist told the inquest: "After about 45 minutes to 60 minutes I understand that he started to become unwell. He asked for his inhaler and he self-administered this.
"However, his condition deteriorated, an ambulance was called, the officers at the scene gave him first aid and he must have arrested as CPR was started."
An ambulance got to the scene at 8.28am and arrived at Stockport's Stepping Hill Hospital at 9.40am, but Mr McGuinness was pronounced life extinct around 15 minutes later.
Asked to comment on whether the stress of the situation may have played a role in Mr McGuinness going into cardiac arrest, Prof Rutty told the jury: "His heart disease had reached a level that could cause sudden death at any time.
"I found no marks to suggest that he had been excessively restrained against his will or was subjected to any form of trauma.
"He could have just had a heart attack at any moment whatsoever.
"The other possibility is that the stress and the situation that he was in, ie the police entering where he was, the handcuffs... caused him to have a heart attack. Anything that increases your blood pressure or pulse rate could tip the balance.
"It isn't possible as a pathologist to go either way. All I can say is that both are entirely possible and both relate to his heart."
The inquest was told there was no suggestion Mr McGuinness was "fighting against" the police or arguing with officers, with him instead being calm and compliant.
During questions put by a lawyer representing Mr McGuinness's widow, it emerged that he was arrested while in bed wearing underpants and was then allowed to remove his handcuffs to put a top on, before being permitted to enter the garden to smoke.
Asked whether it was common sense that Mr McGuinness would have been stressed by what had occurred, Prof Rutty said it was possible that stress had "pushed" him into cardiac arrest.
But the pathologist added: "He is not resisting and that's the complete opposite to the cases which I normally see where they are shouting, fighting, trying to break free. That's not the case here.
"He's an hour into this... and his heart is so bad that he can literally drop down dead at any second."
Both scenarios were possible, Prof Rutty said, adding: "I am very cautious. It could be a event and it could place stress on the heart. But whether it did or not is another matter."
The first day of the inquest, which is expected to finish on Wednesday, was told police body worn cameras were turned off at some point during the incident.
Derbyshire area coroner Peter Nieto told the jury: "You will hear that when the police attended those cameras were working and recording. At some stage those cameras were turned off and you will need to understand why that was."
Mr McGuinness was not charged with anything and was held during the raid under powers allowing "reasonable restraint" during the exercise of officers' functions.
Jurors were told it was the police's intention not to arrest Mr McGuinness unless evidence was recovered which would have justified his arrest.
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