Two black men in their early thirties are stumbling around, leaning on each other. 'They're brothers,' a local tells me. 'They're blind.'

I assume she means blind drunk. One of the brothers then shakes out a white cane and my heart nearly stops. How did they go blind? I ask. 'Nobody knows.' The men are connected with string: the man with the cane holds the string leading his brother through their dark maze by the wrist.

I am travelling with two lawyers. Two months earlier, a drunk Aboriginal man was arrested for swearing at police. Less than an hour later he died with injuries like those of a road-trauma victim. The police claimed he tripped on a step. The community didn't agree and burnt down the police station. The lawyers are here to represent pro bono the Palm Island community in the state government's inquest into the man's death.

The island's chairwoman, wearing a hat crocheted with the Aboriginal flag, collects us from the airstrip and drives us into town along an old road fringing the water. In the township there is a jetty, a beer canteen, a hospital, a long-broken clock tower and one store. Outside the store a child sits in a rubbish bin while another child cools him with a fire hose.

Two white women (teachers, or nurses, or police) are walking briskly in shorts and T-shirts. They look as out of place as I feel. 'Who are they?' I ask the chairwoman. 'Strangers,' she says.

In 1916 the island was, to the government official designated Chief Protector of Aborigines, 'the ideal place for a delightful holiday'. The surrounding shark-infested waters also made it 'suitable for use as a penitentiary'. From 1918, Aborigines were sent to the Palm Island Mission in leg irons, deemed variously: 'a troublesome character'; 'a larrikin'; 'a wanderer'; 'a communist'. Usually they had made the mistake of asking about their wages, or practising traditional ceremonies. In its isolation, the mission became increasingly authoritarian - a kind of tropical gulag with all the arbitrary abuse of power that term implies.

Blacks were not allowed on Mango Avenue where white staff lived. Blacks were required to salute any white person they passed. Whites got choice cuts of meat: blacks got bones. At the cinema, whites sat on chairs carried by black servants, blacks sat on blankets. Permits were needed to fish or to swim. There were garden competitions and European dancing, and those who did not participate were questioned by police. A brass band learnt to play jazz and marching tunes, but failure to attend band practice could result in a jail sentence. Even in the Sixties, a man could be arrested for waving to his wife, or for laughing. A teenager whose cricket ball broke off a short length of branch could spend the night locked up.

In the Seventies, when it became legal for Aborigines to drink alcohol, Palm Island opened a canteen selling beer. For people long used to intense subjugation, it was an opportunity to be literally 'out of control'. It also unleashed a violence that had always been under the surface. Despite evidence that the grouping together of different tribes could be disastrous, over 40 different tribes with incompatible territorial, language and kinship ties were sent to Palm Island. It is now a study of dysfunction taken to its ultimate degree: the island has 92 per cent unemployment; more than half the men will die before the age of 45; 16 young people have committed suicide in eight months. The police, far from being seen as saviours, are the focus of great suspicion and often hatred.

The chairwoman drops the lawyers and me at the community 'motel': a series of spotless rooms with barred windows and no apparent overseer. The motel is next to the locked police compound. Through the high cyclone-wire fence, I can see a group of police in a mess room playing pool with some of the nurses. Two officers drive up and park their van, before heaving an old mattress over the windscreen to protect it from the nightly barrage of rocks.

19 November 2004 must have looked like another grindingly banal day. Shortly after 10am, Senior Sergeant Chris Hurley, 33, the island's officer in charge, and Lloyd Bengaroo, the Aboriginal police liaison officer, were escorting Gladys Nugent, a big, gentle-looking woman, to collect insulin from her partner's fridge. She needed the escort because her partner, Roy Bramwell, had just beaten her.

Hurley waited on Dee Street, where every second house has broken windows, graffiti, children playing in the trash. This was Hurley's natural environment. He had spent most of his career working in Far North Queensland's Aboriginal communities: Thursday Island, Aurukun, Kowanyama, Bamaga, Cooktown, Laura, Pormpuraaw, Doomadgee, and Burketown. All hot, despairing, impoverished places with chronic alcoholism and violence.

Lloyd Bengaroo was in his late fifties, overweight and overburdened. A police liaison officer is meant to work with police, representing the interests of the community, but to many Aborigines Bengaroo didn't convince in the role. He was seen as a police 'watchdog' or 'errand boy' and wasn't much liked or respected.

While the two men waited, Gladys's nephew, Patrick - drunk and high from sniffing petrol - started calling them 'fucking queenie cunts'. Hurley arrested him. Bengaroo held the doors to the police van open.

Cameron Doomadgee walked past. 'Bengaroo,' he said to the police aide, 'you black like me. Why can't you help - help the blacks?' To which Bengaroo replied, 'Keep walking or you be arrested, too.' Doomadgee, 36, a happy-go-lucky character who loved to hunt and fish, had been drinking cask wine and 'goom' - methylated spirits mixed with water. For all he'd drunk he was 'walking pretty good, staggering but not falling over'. He retreated, but when he was 20m away, turned and appeared to say something. Bengaroo didn't hear anything. Others, closer than Bengaroo, reckoned he was singing. But Chris Hurley heard something disrespectful and decided, at 10.20am, to arrest him for creating a public nuisance.

What happened at the police station is disputed: as Doomadgee was taken from the van, he was 'going off, drunk, singing out and everything'. Struggling, he hit the Senior Sergeant on the jaw. Two witnesses say they saw Hurley punch Doomadgee back. In the doorway, the men tripped on a step and landed side by side. Hurley stood and pulled his prisoner into the hallway. He didn't, at the time, notice another Aboriginal man waiting to be questioned.

Roy Bramwell, 29, had been brought into the police station to answer questions relating to the earlier assault of his partner, Gladys, and her two sisters. At the station, Roy says he watched as Chris Hurley dragged Cameron Doomadgee into the hallway: 'Chris laid him down here and started kicking him. All I could see [was] the elbow gone down, up and down, like that... "Do you want more Mister, Mister Doomadgee? Do you want more of these, eh, do you want more? You had enough?"'

Roy's view was partially obscured by a filing cabinet, but he could see Doomadgee's legs sticking out. He claims he could see the fist coming down, then up, then down: 'I see knuckle closed.' Each time the fist descended he heard Doomadgee groan: 'Cameron, he started kicking around and [called] "Leave me go," like that, "now. Leave me go - I'll get up and walk."'

But Roy says Hurley did not stop: 'Well, he tall, you know... Just see the elbow going up and him down like that, you know, must have punched him pretty hard, didn't he? Well, he was a sober man and he was a drunken man.'

Doomadgee was then dragged into the cells. Moments later, Chris Hurley came back and Roy saw him rubbing his chin. He had a button undone. Roy says Hurley asked him if he had seen anything. He said no, and Hurley told him to leave. Roy went to get his social security cheque, along the way telling some friends: 'Chris Hurley getting into Cameron.' They told him, 'Go tell someone, tell the Justice Group.' But none of them did anything. They went on drinking.

The cell's surveillance tape shows Doomadgee writhing on the concrete floor, trying to find a comfortable position in which to die. He can be heard calling, 'Help me!' Another man, paralytic with drink, feebly pats his head. Before he dies, Doomadgee rolls closer to him, perhaps for warmth or comfort. The camera is in a high corner and, from this angle, when Hurley and another officer walk in they look enormous. The officer kicks at Doomadgee - which in court is referred to as 'an arousal technique' - then leans over him, realising he is dead. At 11.22am Hurley called an ambulance. Three minutes later the ambulance crew arrived and determined that Cameron Doomadgee had been dead for at least 20 minutes. The tape records Hurley sliding down the cell wall with his head in his hands. Doomadgee had a black eye, four broken ribs and a liver almost cleaved in two. His injuries were so severe that even with instant medical attention he was unlikely to have survived. Elizabeth Doomadgee, Cameron's sister, is a handsome woman in her early forties with an almost stately quality. She does not have a telephone, and one evening before the inquest begins two lawyers and I drop by her house unannounced. Elizabeth invites us for dinner.

We sit down at a table on the veranda that she covers with a purple batik cloth, and upon it she lays the household's best food: a large economy packet of biscuits; two bowls full of fruit. Small children use this opportunity to sidle up and eat freely. Ten-year-old Sylvia, Elizabeth's youngest child, tells me a secret: there is a plug on Palm Island, and if there were ever a war the elders could remove it so that the island would disappear. What would happen to all the people? I ask her. 'They'd swim,' she says, as if I must be crazy.

The Doomadgees were sent to Palm Island in the mid-Fifties after their father, Arthur (a Gangalidda man) punched a missionary at Old Doomadgee, in the Gulf country of North Western Queensland. Doris, his wife - of the Wanyi people - had 10 children, of whom, Cameron's sister Jane tells me, 'only three are dead'. Five of the surviving sisters live on the island, and on the day Cameron was arrested Carol, the eldest, went to the police station 'to take feed for him'. Although her brother had been dead for two hours, Hurley turned her away, telling her to come back at 3pm. Later, in the afternoon, a policeman from the mainland visited the family. 'The detective had a red book with him,' Carol recalls, 'and he read it out to us telling us we lost Cameron.' Two weeks later, their mother died. Mothers, Elizabeth tells me, will always try to protect their sons: her mother was following Cameron to the afterlife to look after him.

Two large bowls of stir-fried wild goat and rice are brought to the table. The goat, I later realise, was hunted by Cameron. Elizabeth thanks God for the food on the table and prays for those who do not have as much as her family. In a room with no furniture, people sit on the floor watching Shrek on television. Elizabeth prays for Sylvia's sore foot to heal, and for any children in hospital: 'May God with his great hands heal them.' She thanks God for our being in her home: 'Only you know what's in their hearts.' She prays for the lawyers' mouths, so that at the inquest they are bold; and for my ears, so I don't miss any important details.

Three plates are laid on the table, and only the lawyers and I are served. It is humbling to enjoy a dead man's bounty. Only after we refuse second helpings do the rest of the family also eat. Later I step into the kitchen and there are at least 10 others enjoying small portions. Among them is Eric, Cameron's 15-year-old son, a quiet, polite boy wearing a basketball shirt.

We ask Elizabeth how she will feel seeing the police give evidence: 'I'll forgive them what they done, because Jesus said love thy enemy.'

'If you say that then it doesn't matter what happens,' one of the lawyers suggests.

'It doesn't matter,' Elizabeth answers, 'because it's in God's hands.'

'I'm not that patient,' he replies.

Elizabeth tells us that Aboriginal people have no choice but to be patient. 'If I didn't have God in my life...' she says, then pauses. She has something else in her life: 'blackfella' protocol. She could put a curse on Lloyd Bengaroo. She could take an item of clothing off his washing line and send it to her relatives in the Northern Territory. They would make sure he'd grow sick and die. But she tries to love him and to be patient. In prayer meetings, she has been praying for justice. 'We want justice for Cameron, to make his spirit free. We want the truth. We want to hear the truth.'

That night the lawyers and I walk to the jetty. It's 11pm and people sit along the jetty's edge holding their fingers, with baited string attached, above the water. ('What are you fishing for?' one of the lawyers asks a young man. 'A fish, mate, any fish I can find.') Predominantly they are women and children. One child lies in the centre of the jetty asleep on a pillowcase; others are dozing in their strollers. Perhaps it is safer to bring them out, away from the drinkers.

We meet three boys who look 13, but claim to be 16. A cigarette butt is tucked behind one boy's ear. When he manages to light it, the three share the stub. 'Miss, what song you like?' he asks. They like Eminem, Usher and Destiny's Child. Michael Jackson is 'Sharpnose'. One boy performs a dance routine. Another shows us some punches he's learnt in boxing. The third boy makes birdcalls with his hands. We start to walk back to the motel and the boys follow. Someone gives a coin for each time a rock hits the old, long-burnt clock face and not one shot misses.

'What do you do for sport?' one of the lawyers asks. 'Throw rocks at coppers.'

Headlights warn a police van is approaching and the boys bolt before we can say goodbye.

Local witnesses will give their evidence on the island. The police - for security reasons, it is argued - will give theirs on the mainland in Townsville. Court convenes in the local gym. About a hundred locals attend, but most sit at the back or stand close to the door where it must be impossible to hear. Only the five Doomadgee sisters sit in a line at the front, wearing their best clothes and holding kitchen wipes in case they need to dry their eyes. Seemingly from nowhere, their brother's dog arrives and sits beside them. Later, Elizabeth tells me the dog bit a witness who gave unfavourable evidence.

It is distressing to watch the Aboriginal witnesses being examined and cross-examined. They are asked to read through and swear by their statements, which is impossible for the many who are illiterate. They are questioned about the timing of events, but few wear watches. They are asked leading questions in complicated legalese and some of them, confused or intimidated, try to guess the right answer.

'No wonder so many of our people are in jail,' one woman says. Aborigines make up two per cent of the Australian population, but are 15 times more likely to be jailed, and they account for one-third of all deaths in custody - so far no police officer has ever been charged.

Seventeen lawyers are lined up along the bar table, and all but Andrew Boe, the Burmese-born lawyer working for the Palm Island Council, are white. The Doomadgee sisters rely largely on their lawyers' facial expressions to gauge what is happening. 'Black man pretty hard to understand white man's language,' one witness tells me. Likewise, often the lawyers can barely comprehend the Palm Islanders. One thin, barefoot woman breaks down mid-testimony and sits with her head in her hands, distraught because no one understands her. Another witness, labelled a liar by the police lawyers, goes home that evening and tries to set himself alight.

More dogs arrive to lie in the shade. Children collect the empty water bottles the lawyers leave lying around. As the day wears on, I can feel myself nodding off. Earlier, I had accompanied Elizabeth and a lawyer on a drive to encourage witnesses to stay sober. We'd stopped by a house shuddering with loud dance music. Teenagers, all of them wasted, started to crowd around the car. One girl put her hand to the car window, staring in, and clearly saw no one. Beer cans lay all around; small children were underfoot. It was nine o'clock in the morning.

In the makeshift court, Roy Bramwell is now the star witness. He has been reading his police statement every day, trying to memorise it. 'It's like a daily prayer for him,' Elizabeth says. But Roy's examination begins badly. Although this is supposed to be an inquiry into the truth, not the worth of Roy's character, there's no forgetting that he was at the police station because he'd just bashed three women. If this ever went to trial would anyone believe him?

Roy says he saw Hurley punching Doomadgee, and the police lawyers work hard to discredit his testimony. Roy gets aggressive because he feels the lawyers 'put it all together and twist it'. His frustration is palpable. Unbidden he stands up to show what he saw. Roy rests his knee on the ground, as he alleges Hurley did, and punches. For a moment, everything is silent: it is clear that a big man's knee to the chest of someone pressed against a concrete floor would cause extreme injuries. Quickly, the court is adjourned.

The inquest soon becomes bogged down in legal argument about releasing Hurley's police records. It emerges there are 20 to 30 official complaints against him, of which he has always been unequivocally cleared. Hurley has, however, sometimes investigated these complaints himself.

I meet one woman who claims the Senior Sergeant ran over her foot then, according to witnesses, left her lying by the side of the road. Her bone was broken and sticking through the skin. Hurley disputes her account of what happened. Later, in court, three doctors tell the inquest these injuries are consistent with the woman's story. The island's doctor, who had first examined her, recalls telling an anxious Hurley it seemed she had indeed been run over. But Hurley claims the doctor told him at the time that it was highly unlikely that a car wheel was the cause of the injury. He immediately called his superiors, assuring them the doctor believed the damage was most likely done by the woman kicking the ground.

It's several months before the police involved in Doomadgee's death are required to give evidence at the inquest. People have travelled from far away, they say, to look Senior Sergeant Hurley in the eye. This heightened expectation is the antithesis of the police attitude. They sit outside the courtroom in riot gear, flicking through magazines. 'This is an example,' one senior sergeant tells me, 'of people trying to look for the worst in a situation.'

When Hurley arrives, amid much excitement, it's like glimpsing Colonel Kurtz. He comes through a back door to avoid photographers. A tall, rugged man, he could be straight from casting as the sheriff. His police uniform is carefully pressed. Each crease is visible. He is clean shaven, tanned, calm, polite. It goes to make him a good witness. He calls Counsel Assisting the Deputy Coroner, Terry Martin 'Sir', and looks him straight in the eye. He keeps very still.

Martin: 'Do you have friends who are Aborigines?'

Hurley: 'Yes, sir.'

Martin: 'Do you have anything against Aboriginal people?'

Hurley: 'No, no. I wouldn't have, I, I wouldn't go to those communities if I had some something against Aboriginal people, I, I couldn't serve in those communities.'

Martin does not ask him why he goes to 'those communities'. Why would you choose to be despised?

Previously I spoke to a highly regarded police inspector who served on Palm Island for six years. Early in his tenure he'd been viciously beaten, but decided not to be transferred, winning great respect. 'I saw violence mainstream people can't understand,' he tells me. And living on an island 'was like living in a fishbowl. There's no escape.' Still, the inspector claims, those were the best years of his life. He had a sense of being able to make a difference. Days seemed more vivid, more intense, somehow life was closer to the surface. But can you step into such dysfunction and desperation and not be affected in some way? Becoming a cop is a way for a man without a lot of education to gain a lot of power.

'I was like the king of the island,' the inspector recalled. I suggested this was the temptation some officers succumb to - the community becomes their fiefdom. 'No,' he said, perhaps not understanding my meaning. 'It was just that it was my place.'

Martin takes Hurley back to the morning of 19 November 2004. Within the first few minutes, the Senior Sergeant claims privilege against self-incrimination. None of the testimony he gives will be admissible should he ever be charged in relation to the death.

Under privilege, Hurley describes Police Liaison Officer Lloyd Bengaroo's feelings after Doomadgee challenged him about not 'helping the blacks'. 'His pride was hurt,' he says. Hurley would have the court believe that he arrested Doomadgee to save Lloyd's honour. But in a place where alcohol consumption dominates life, Martin asks Hurley why he could not have just driven the drunk man home. Doomadgee was not known for being violent or a troublemaker, and could have been taken to a safe place to sober up, rather than to the police cells.

Martin then leads Hurley to the moment Doomadgee punched him. The Senior Sergeant claims he was not angered by this, but 'annoyed'. And in this state he struggled with Doomadgee, until both men tripped through the station's doorway.

Martin: 'You didn't land on top of him?'

Hurley: 'Well, I now know that medical evidence would suggest that. That I landed on top of him. If I didn't know the medical evidence, I'd tell you that I fell to the left of him... I mean, life doesn't unfortunately go frame by frame, and if it did, I would've been able to give a 100 per cent accurate version. But the version I gave was my best recollection and the most truthful. It was the truth that I thought.'

Martin reminds Hurley that in three previous police interviews he said he fell to the left of Doomadgee. This is what he said on the afternoon of Doomadgee's death; the day after; and a few weeks later. There would now seem to be only two possible explanations for Doomadgee's black eye and massive internal injuries, Martin claims: that Hurley had indeed fallen on top of him, or that Hurley had struck a series of forceful blows. Since he has repeatedly denied the former - until knowing of the medical evidence - could the latter be possible?

The 1989 Royal Commission into Aboriginal Deaths in Custody recommended each death be treated as a homicide, and that police should not investigate other police, to avoid 'collaboration and dare it be said collusion'. But 15 minutes after the paramedics pronounced Cameron Doomadgee dead, Senior Sergeant Hurley called his good friend, Detective Sergeant Darren Robinson. The men had served together on the island for the past two years and Robinson had previously investigated and cleared Hurley of other complaints. After the men spoke, Robinson then called two other officers who had also worked closely with Hurley before and held him in high regard.

It must have been reassuring for the Senior Sergeant that he, the main suspect, would be investigated by old colleagues and friends. He picked the detectives up from the airport and drove them round to the relevant areas of interest. That night, Robinson cooked dinner at Hurley's house for the detectives. Meanwhile, no part of the police station was made into a crime scene or sealed off. No areas were tested to see if there were matches with the blood from Doomadgee's eye. No photographs were taken of Hurley's hands or boots. The transcript of Hurley's police interview is striking for its camaraderie: the chief investigator refers to Hurley as 'mate' or 'buddy'; Hurley calls him 'boss'.

In the courtroom I notice the women from Palm Island. Some of them look much older, 20 years older, than they are. All of them are mothers with lost sons. Mothers with sons in custody; sons who have died in custody; sons in trouble with police. They sit in the airless room emitting a low drumbeat of heartache. The Doomadgee sisters sit among them, waiting for something to happen. 'This just drag, eh,' Valmai Doomadgee says, but she believes her brother is watching over her. 'It's like he there telling me to keep pushing, don't give up.' Next to her sits Elizabeth who is trying, I imagine, to love her enemies.

Father Tony, Palm Island's Catholic priest, says that among families ravaged by alcoholism and violence, a completely different concept of forgiveness exists. He was with Elizabeth recently when she spoke at a Townsville church service. She told the story of her brother's death and a policeman stood up and started to cry. He said he'd seen terrible things done to black people and how sorry he was. 'He cried broken-hearted,' Elizabeth tells me. She went over and hugged him: 'Brother, I forgive you.'.

· The Coronial Inquiry into Cameron Doomadgee's death has finished taking evidence from all relevant witnesses. The Deputy Coroner is waiting to hear final submissions, and will deliver her findings as soon as possible