'My son didn't kill himself. He wouldn't have given the police that pleasure, he wouldn't have let them beat him," says Margaret Brady. "And he loved me far too much to end his own life. He knew that would have destroyed me."

We're in the living room of a terraced house in Strabane. Upstairs, Margaret's son John lies in a coffin. He's wearing a football shirt – his beloved Liverpool. But the emblems of his other passion are all around. A Tricolour drapes the body. His black gloves and beret sit on top.

John Brady was found hanging by his laces in Derry's Strand Road police station last weekend. He was 40 years old. He'd spent almost half his life in jail. The early years were for republican offences, including the murder of a policeman. The last five years were effectively internment, his family say. Brady had been convicted of nothing.

A small group of supporters had fought a long campaign, with no mainstream political support, to have him freed. Finally, they succeeded. Brady was to be released permanently next month. He had started weekend parole.

Then on Friday 2 October, he was arrested. He was questioned about assaulting and threatening to kill his brother-in-law earlier that day, which he denied. Police held him overnight and were about to charge him. So could John Brady not face another long stretch in prison or did something more sinister happen last Saturday in Strand Road barracks?

At the wake, nobody believes Brady killed himself. "Suicide would have been alien to him," says close friend Paddy Brown.

The house is overflowing with mourners. Not just Northerners: republicans from Dublin, Cork, Kildare, Limerick, and Monaghan are there. Around 100 people queue outside on a bitterly cold night to enter the wake house. Women serve them sandwiches and tea.

'I waited so long for him to come home'

"Come upstairs," someone tells the Sunday Tribune. We pass a dozen men and women in white shirts, black ties and trousers in the hall and landing. "Wait here a minute sir," our photographer is asked. And then we enter the bedroom where Brady lies, a crucifix above the coffin, a Tricolour harp-shaped wreath at the side.

Four men in balaclavas, combat jackets, black trousers and boots stand guard. Two hold .32 handguns; one an AK47. The room says so much about the North's complexities. The harsh paramilitary world softened by the humanity of a republican's everyday life – the Liverpool curtains and light-shade Brady bought while on parole. Amidst the burning candles and red roses, Margaret has placed cards her son sent from prison. One shows a picture of a bear. 'Missing you, just can't bear it when we're apart,' it says.

Margaret starts crying: "I waited so long for him to come home but not in a coffin. Had John been killed on active service, I wouldn't have complained. To die in a police station when he'd done nothing wrong is different."

They're a strongly republican family, John Brady's sister Lorna says. "My father was an IRA prisoner in Portlaoise in the 1980s. Growing up, John was like a daddy to me. When I was six, he took me to see Santa. Not many 14-year-old boys would do that for their kid sister."

Brady joined the IRA at 16, his mother recalls: "He said to me, 'If you love me, you'll let me'. And I did. Republicanism is born into you." Brady was jailed for life for murdering RUC man David Black in 1989. His brother Ben and his mother were charged with withholding information.

"It's hard as a mother to stand between your two sons in the dock," Margaret says. "But John said, 'Hold your head up high mum', and I did and I was proud of my sons." Ben received four years imprisonment; Margaret, a two-year suspended sentence.

John Brady was freed on an early release licence under the 1998 Belfast agreement. He joined Sinn Féin but became disillusioned, accusing the leadership of "selling-out". He joined the Real IRA.

In 2003, he was arrested with two women by the PSNI near the Donegal border. Guns were recovered from the car. The trio were charged but the case was later dropped. The Real IRA claim this was to protect an informer whose identity they know.

The two women were freed from jail but not Brady. "His early release licence was revoked," says Lorna. "But his case went before the Life Sentence Review Commission and it looked very positive. Then, out of the blue, he was charged on low copy DNA evidence with trying to kill a soldier in Tyrone in 2002.

"After low copy DNA was discredited in the Omagh bomb trial, the case against John was dropped. Once again, he faced no charges yet they wouldn't let him out of Maghaberry jail." He was never depressed, his mother says: "It wasn't hard visiting him. Other visitors would cry as they left prisoners who were feeling low. Never us because John was always smiling."

Frustrated that he remained in jail without charge, Brady asked the welfare group for Real IRA prisoners to take him off their list. Then, he requested to be transferred from the republican to the ordinary criminal wing. "He cut all ties with the republican movement," says Marian Price of the 32 County Sovereignty Movement. "He'd no other choice because the authorities were using everything to keep him in jail. And he understandably wanted to get out and lead a normal life."

For the past five weeks, Brady had been granted weekend parole and was to be permanently freed next month. "My war is over," he told friends in Strabane. He remained a political republican but believed 'armed struggle' wasn't the way forward. Then last weekend, he became entangled in a family dispute.

Brady's older sister Martina is married to political cartoonist John Kennedy who has had work published in the Mirror and US publications. Kennedy is known for his radical politics and some cartoons have been critical of the PSNI.

Argument

The Kennedys and the Bradys fell out two years ago. Margaret Brady claims she hadn't been allowed to see her grandchildren. Even presents and cards were returned.

Around 3pm on Friday 2 October, John Brady was collecting a friend's children from Strabane's Barrack Street school.

An argument developed with John Kennedy who was collecting his child. Afterwards, Brady immediately informed those in charge of his prison pre-release scheme about the incident and offered to return to jail, his family claim.

He was reportedly told to contact the PSNI with details of the altercation. Brady's family say he rang police who asked if he wanted to lodge a complaint about John Kennedy. Brady said no but asked for the incident to be logged.

At 8.30pm the PSNI arrested Brady. John Kennedy had reportedly made a complaint. "My brother phoned me twice from the barracks," says Lorna. "He was in good form. I went to Strand Road on Saturday afternoon with a change of clothes for him. I sat there for two hours but wasn't allowed to see him."

Brady's solicitor, John Finucane, arrived at Strand Road at 9.30am. He found his client was his usual relaxed self. He was wearing a Liverpool shirt. Being a Man United man, Finucane joked had he known Brady's team, he'd not have come.

Finucane believed police didn't have the evidence to charge Brady, who denied assaulting or threatening to kill Kennedy. Brady said he'd three witnesses supporting his account of the altercation. He gave police their contact details. Although Brady had been under arrest for almost 20 hours, he was questioned for just 42 minutes.

At 4pm, Finucane was informed his client was to be charged. He didn't detect any panic in Brady. As a solicitor he'd learned to read, through changes in their demeanour or expression, if somebody is vulnerable. At 4.35pm, Finucane left Brady in the legal consultation room and went to talk to police.

He was away 15 minutes, 20 at most. When he returned, he found Brady hanging by his trainer laces from the window. He called out to police. Paramedics tried to revive Brady but it was too late.

Finucane has serious questions about why Brady was arrested in the first place. He believes had a complaint been made about anyone else, they would simply have been asked to visit a police station at an agreed date, not arrested in that manner. He also believes Brady was being charged before the investigative process was adequately followed through. The young solicitor, whose father Pat was murdered in 1989, broke the news to the Bradys. "John Finucane rang and said he needed to see me," Lorna says. "I met him in the Asda supermarket carpark and he told me my brother was dead."

On hearing of her son's death, Margaret Brady took down photographs of her daughter Martina – John Kennedy's wife – from her home. Although those of the three Kennedy grandchildren remain on display.

"I'll pray for my daughter every day of my life but I'll never speak to her again," Margaret says. "In the republican world, you involve the police only for rape or child abuse. You certainly don't complain about prisoners on licence. Her father would be turning in his grave."

Margaret asked an intermediary to tell the Kennedys, who live only 100 yards from her, that it would be best if they left Strabane. "It wasn't vindictiveness. Feelings were running high. I was worried what locals might do. I'd three grandchildren I love in the house and I wanted them safe."

Left the North

The Kennedys have reportedly left the North. The Sunday Tribune contacted John Kennedy by email for comment but received no reply. But the main questions concern John Brady's treatment in Strand Row.

The family want to know why he was still wearing his trainers and why police didn't immediately return him to his cell when Finucane left the legal consultation room.

Derry republican Gary Donnelly has been questioned many times in Strand Road: "Every time you're brought in, you must remove your shoes, belt, and jewellery. I've even been asked to remove the drawstring from tracksuit bottoms.

"It's standard procedure so a prisoner can't harm themselves or a cop. Why didn't this happen to John? And it's bizarre that he was left alone in the legal consultation room, one of the only spots in the barracks without a camera. Every time my solicitor has left the consultation room, the cops have thrown me back in a cell."

The PSNI is tougher in Derry, with its strong dissident presence, than in other parts of the North, Donnelly says. He has been assaulted several times by police.

Ex-INLA prisoner Willie Gallagher knew Brady well. "I saw John last week and he was as upbeat as ever. He was hoping to move to Donegal when he got permanently released because he said the PSNI would never give him peace in the North. He was planning computer classes. I don't believe he killed himself. But, even if he did, the PSNI drove him over the edge and as an organisation, are responsible for his death."

The Bradys have no faith in the Police Ombudsman's investigation into the matter. While John Brady's war was over, ironically his death has increased republican feeling.

In the front windows of republican homes in Strabane, the 'Free John Brady' posters, erected years ago, remain. Now they're joined by black flags. And on the walls, there's fresh graffiti: 'John Brady is free. RIP Chara.'