Mark Duggan's father died earlier this month, his demands for justice unsatisfied. He will never know the circumstances that led Metropolitan police officers to shoot dead his 29-year-old son last August – a killing that sparked one of the biggest outbreaks of civil unrest in English cities for generations.

"The truth is that we're 11 months down the line now since that night, and we still don't know what happened," says Stafford Scott, a race advocacy worker and a friend of the Duggan family for nearly 30 years.

A former advisor to the Metropolitan Police's black gun crime Trident unit – until he gave up after concluding "we were just being used to tick a box" – Scott was told of the incident by a police officer on his way to the scene. Initially, the Independent Police Complaints Commission stated that they "understand the officer was shot first before the male was shot"; the IPCC would later admit a "mistake" had occurred. There had been no shoot-out.

The four days of rioting that soon followed ended with five deaths and some of the worst urban destruction in England since the Blitz. In Tottenham, at least, a bitter history of racism and a deep-seated resentment of the police fuelled an eruption that was as chaotic as it was unexpected.

There is no shortage of distrust of the police in Tottenham, and the Met's response to the Duggan shooting brought long-simmering tensions to the fore. Officers had failed to even inform the family of their son's death. "I had a better inside track than the family who had lost their son," says Scott. "And that can't be right."

With police officers still refusing to speak to the family two days later, a peaceful demonstration at Tottenham police station led by friends of Simone, the mother of Mark's three children, grew increasingly restless. When Chief Inspector Ade Adelekan arrived, he was met with boos and cries of "murderer", "Uncle Tom" and "coconut".

Adelekan made a number of calls for help to Ken Hinds, a leading figure in Tottenham's black community and chair of Haringey's Stop and Search Monitoring Group, which was set up by the police based on recommendations from the Stephen Lawrence inquiry.

Hinds recalls the Duggan family finally meeting Adelekan and demanding a more senior officer, leading the Chief Inspector to walk away to contact his superiors. "I thought – oh my God," Hinds recalls. "When it [gets] dark, nobody's got any control." Many of the women – some with young children – had been waiting outside the station for hours. "So they decide to go," recalls Scott. "And at that point the young men start to show signs of frustration." Forty minutes after the meeting with Adelekan, the disorder began.

The fury over Mark Duggan's death was deeply felt, but the grievances that drove the riots were far broader – and continue to fester a year on. Many in the local community simply did not trust the police to begin with, and so it remains.

"The expectation of no justice is a dangerous place to be in," says Symeon Brown, a youth community worker in Tottenham. "It essentially means 'we do not comply, we do not consent', that is essentially what a riot is, and that can have devastating consequences for communities."

Mark Duggan was the fourth black man or woman to die at police hands in the Borough since the 1980s: the others were Roger Sylvester, Joy Gardner and Cynthia Jarrett – whose death sparked the 1985 Broadwater Farm riot; 1,433 people have died after contact with the police since 1990. Not a single officer has been convicted of manslaughter. "You've had other people who've been the victim of police brutality before, and they've had no justice," says Mr Brown. "We don't expect justice."

The attitude of young people in Tottenham towards the police is shaped by the experiences of their parents and their grandparents. Any negative incident with police officers taps into an intense bitterness passed through families, going back decades. "The average young person in Tottenham believes that the police discriminates against them, oppresses them and harasses them," says Scott. "But that isn't just the experience of young people in the 21st century; it's the experience of young people from the 1950s and 1960s... when black people moved into this community."

Scott was first arrested and fined £30 under the so-called "sus laws", part of the Vagrancy Act passed in 1824 which allowed the police to arrest anyone who might intend to commit a criminal offence. It was not repealed until 1981, but large numbers of black men were criminalised by it. "Hundreds of kids, if not thousands, from the same community were criminalised and kicked out of schools in the 1970s and 1980s," says Scott – and of course, many of them are the fathers of young people in Tottenham today.

It is this inheritance that ensures the relationship between black people in Tottenham and the police is "extremely strained", says Hinds. "You've got three generations of the black community that has been affected the same way around stop and search, which means what I experienced 35 years ago is being experienced today by my grandson."

Black people are now 30 times more likely than white people to be stopped and searched under Section 60 of the Criminal Justice and Public Order Act 1994. Kazan Allen, a 17-year-old art and design student at Highbury and Islington college, has been stopped and searched countless times. "Sometimes they're a little bit rude, they get a bit touchy-touchy," he says. "People don't like it. They don't give us the respect that we need."

For Samantha Porsche, a 16-year-old finishing school and looking for work, there was a sense that the police "always see us as bad kids". She has no doubt it was this that drove the riots on. "They wanted to find an excuse to go against the police, the government. They're always against us kids."

Leandra Alexander-Cotter, a 19-year-old studying sociology and social policy at Nottingham University, recalls an occasion in which two male friends walked her and another friend home. "A whole police van came over and stopped us, and they believed that – even though they were my friends – these guys were doing something wrong, that they were with me for negative reasons."

It infuriated her, because she felt that a commendable act by two young men had been transformed into something incriminating. "It's like it's guilty until proven innocent."

It wasn't just race, though: class was creeping in too. "If you dress a certain way, if you're conforming to the middle-class norm, it's not as big a problem as if you dress the way people dress locally," she says. She has no belief in the police as being on her side. "I think the police are here to protect the Establishment, not to protect the people in this area," Alexander-Cotter says.

Drawing on his experience as a youth campaigner, Symeon Brown says young black men are "overpoliced as suspects, and underpoliced as victims". But the impact could be subtle, he says. "You're aware you're being 'othered'. You're aware that you're almost an enemy within the state, you're a kind of danger."

It is this feeling of not being treated like everybody else – or "not given full status as British people", as Brown puts – which makes so many young people in Tottenham regard the police as a hostile force.

According to Hinds – who works closely with the police – some officers appear to promote the idea that they are the biggest gang in the area. "We're the biggest gang. We've got 30,000-odd people," is the impression they give, Hinds says. "When you say 'I'm a gangster too, and we've got bigger guns than you, and we're going to do this, that and the other', that's bringing it on."

Although there are plenty of stories from young people of perceived police harassment, older members of the community are keen to back them up. Arlene Lewis, 44, who works in local housing provision, insists the police pick on young black men. "They do. I've seen it – and I'd call it first-hand harassment." Dennis Campbell, 48, who is unemployed, hasn't been stopped and searched for years, but believes young people feel justifiably harassed by the police: "I was walking down here the other day, and there was a couple of guys, and one of them said he'd been stopped and searched 18 times in one week."

A widespread belief that the police are like "an occupying force", as Hinds puts it, combined with a lack of any secure future for many young people, lies at the heart of what happened last summer. Neither issue has been addressed since.

More than half of young black people are now unemployed: the number has nearly doubled since Lehman Brothers collapsed in 2008. In the borough of Haringey, where Tottenham is located, 75 per cent of funding for youth services has been slashed. Looking back at the riots, Campbell sees a "lack of jobs, lack of hope, lack of everything".

It is not difficult to encounter that despair on the streets. "Kids were bored and they were looking for a reason to start something, and the shooting gave them a reason," says David Cooper, a white 18-year-old art and design student who feels harassed by the police because of how he dresses. "There's nothing for us kids to do. Clubs, chill-out places, they're closing them down." He can't find work either – he says that after applying for a hotel job, "once they heard I was from Tottenham, they dismissed my application".

"I think everyone was just fed up really at the way they were being treated," says 21-year-old Keith Addae, who is about to start studying creative writing at Greenwich University. "I've always said that if you push someone far enough, they're going to end up pushing you back some day."

But grievances against the police were not, on their own, enough to produce the scenes we saw in Tottenham last August. "I think it was just the culmination of frustration in the community," says Ms Alexander-Cotter. "And they just felt they were treated unfairly, not just by the police, even though I swear it was targeted towards them – but by society as a whole."

With the situation facing young people in Tottenham worse than it was a year ago, questions have to be asked about whether we have seen the last of the disorder. The relationship between the local community and the police seems unsustainable.

"I do think there needs to be a communication about why they're doing stop and search," says Seema Chandwani, a 34-year-old youth worker and former deputy head of Haringey's youth services. "Because I don't think in their right mind anybody wants to allow people to walk around with knives or to walk around with guns or for their little brother or son to be stabbed because the police weren't doing their job, so it's about finding that balance." Hinds is in no doubt that, if this balance is going to be achieved, there has to be a change in police training, which fails to "differentiate between the real gangster and the people who just go about doing their regular business".

"The police need wider society to have faith in them, because they're the ones who are meant to protect society," Stafford Scott argues. "But they don't understand that their behaviour undermines that notion in communities like mine." It is difficult to see how anything other than a radical new approach on the part of the police will overcome decades of antagonism.

The sense of growing despair at an increasingly insecure future must surely be overcome, too. "You can't have an ambition these days," Cooper says, "I just want to get a job and live comfortably, and that's it."