A man is handcuffed and led away by a Missouri State Trooper during demonstrations in Ferguson, Missouri, in August 2014. Credit:Bloomberg "Some of those protesters were right," he said. The report, which Mr Holder called "searing" described how police officers targeted African Americans in street and traffic stops, and that in some cases competed with one another to issue the most number of citations for a single infraction, and how city officials had boasted that the fines they issued were higher than those by neighbouring jurisdictions. It showed how local courts then ensured that African-Americans did not have those fines voided. The statistics are shocking. The report shows that 85 per cent of people subject to vehicle stops by Ferguson police were African-American; 90 percent of those who received citations were black; and 93 percent of people arrested were black. This while 67 percent of the Ferguson population is black.

A police tactical team moves in to disperse protesters in Ferguson, Missouri, in August 2014. Credit:AP It further found that 95 per cent of people ticketed for jay-walking were African-American, and 94 per cent of those charged with "failure to comply" of "failure to obey" were African-American. In local courts African-Americans are 68 per cent less likely to have their cases dismissed by a Ferguson municipal judge. A car passes a memorial in Ferguson this week for Michael Brown, who was shot and killed by police officer Darren Wilson last year. Credit:AP Further it found that city officials sometimes simply closed the facilities for people to pay their fines, then increased penalties.

Mr Holder described a case in which one African-American woman was issued with two parking fines totaling $US152 ($194). During her struggle to pay she incurred further fines, spent six days in jail, paid $US552 and today still owes over $US500. Attorney General Eric Holder speaks at the Justice Department in Washington. Credit:AP He described the case of man cooling off in his car by a park after a game of basketball when police approached, claiming they suspected him of being a paedophile because there were children in the park. He was fined for eight difference offences, including lying to police because he had given his name as Mike rather than Michael. He went on to lose his license, which in turn cost him his job. Mr Holder said that he understood why the Michael Brown shooting had prompted such a violent response, even if police had not broken the law in the shooting itself. A man wears a tie decorated with a picture of Michael Brown during Brown's funeral at Friendly Temple Missionary Baptist Church in St Louis in August 2014. Credit:AP

"Of course, violence is never justified," he said. "But seen in this context – amid a highly toxic environment, defined by mistrust and resentment, stoked by years of bad feelings, and spurred by illegal and misguided practices – it is not difficult to imagine how a single tragic incident set off the city of Ferguson like a powder keg. "In a sense, members of the community may not have been responding only to a single isolated confrontation, but also to a pervasive, corrosive, and deeply unfortunate lack of trust – attributable to numerous constitutional violations by their law enforcement officials including First Amendment abuses, unreasonable searches and seizures, and excessive and dangerous use of force; exacerbated by severely disproportionate use of these tactics against African-Americans; and driven by overriding pressure from the city to use law enforcement not as a public service, but as a tool for raising revenue." The report also described a series of obscene racist jokes found on the city's email system. Last month the St Louis County Prosecutor Bob McCulloch decried Ferguson's practice of filling public coffers through ticketing as immoral.

"If you think that taxation of our citizens through traffic enforcement in St Louis County is bad, you have no idea how bad it is," he said during a panel discussion last month. "It decreases our legitimacy in law enforcement when they think the only that the only thing police officers are out there for is to write tickets and bring it back to their city coffers. It is immoral." Since the riots the Ferguson mayor, James Knowles, has been criticised for insisting there is no racial divide in his town. The Justice Department will now seek to work with the Ferguson police to reform its practices, though there has already been speculation that the mayor, police chief and city manager will be forced to resign. "In the days ahead, the Department of Justice will stay true to my promise, vigilant in its execution, and determined in the pursuit of justice—in every case, in every circumstance, and in every community across the United States," Mr Holder said.