The parents of murdered black teenager Michael . Brown have announced their plan to file a civil suit against the city of Ferguson . It comes a day after the U.S. Justice Department refused to prosecute Wilson despite compiling a 350,000-page report on racial profiling in the Missouri city that 'led to ' Brown 's fatal shooting at the hands of a white police officer on August 9 , 2014 . 'He did not have to kill Michael Brown , ' attorney Daryl . Parks said of Ferguson police officer Darren Wilson . Taking action : Michael Brown 's mother , Lesley McSpadden , far right , leaves the FBI offices in St. Louis after meeting with federal officials on Wednesday before announcing plans to file a civil suit against Ferguson . Brown 's mother , Lesley McSpadden , and his father , Michael Brown Sr. , attended the news conference at Greater St. Mark Missionary Baptist Church , but they did not speak nor take questions . Parks said the DOJ report makes it clear there are 'rampant , wholesale , systemic ' problems in the Ferguson police department that need to 'change soon for the safety of the citizens . ' He did not say specifically when the suit would be filed . He said only that , 'soon means soon . ' The announcement is a reaction to the news on Wednesday that federal investigators found a pattern of discriminatory and . illegal actions against African-Americans by the Ferguson Police . Department . The report said police in the St. Louis suburb of Ferguson . overwhelmingly arrested and issued citations to blacks to boost . city revenues through fines and court fees , creating a culture . of distrust that exploded on August 9 when Wilson killed Brown . Attorney General Eric Holder said the report showed police created a 'highly toxic environment ' in Ferguson . Catalyst : The Justice Department began the civil rights investigation following the August shooting of Michael Brown ( left ) , an unarmed black 18-year-old , by white police officer Darren Wilson ( right ) Justice Department staff interviewed hundreds of average citizens as part of the six-month probe , concluding that a large portion of Ferguson 's population mistrusts the local police force and considers it illegitimate . Report will show that 88 per cent of people against whom police used excessive force were African-American . 'Let me be clear , this type of behavior will not be tolerated in the Ferguson Police Department or in any department in the city of Ferguson , ' the city 's mayor James Knowles said at the conference . Seven emails included in the report showed police and court officials making racist jokes , including one that said Obama would n't remain president long , remarking 'what black man holds a steady job for four years . ' The mayor did not take any questions at the presser , and though Ferguson Police Chief Tom Jackson had been expected to attend , no explanation was given for his absence . The Justice Department investigation into Ferguson police began immediately after Brown 's killing in August . Analysis of more than 35,000 pages of police records found racist comments from officers as well as statistics that showed African-Americans make up 93 percent of arrests while accounting for only 67 percent of the population in Ferguson , an unnamed department official said . The Department of Justice report also found that 88 per cent of people against whom police used excessive force were black . Not tolerated : Ferguson Mayor James Knowles announced the firing of one police department employee identified among those who sent racist emails . According to figures recorded between 2012 and 2014 , blacks were also twice as likely to be searched than whites during traffic stops , though contraband showed up more during searches of white drivers . Holder also said that charges for minor violations such as 'manner of walking in roadway ' disproportionately affected black residents and were used 'not as a public service , but as a tool for raising revenue . ' Nationwide protests of police actions that resulted in deaths of African Americans in Ferguson , New York and Cleveland laid bare racial tensions and what President Barack Obama called 'simmering distrust ' between police and communities . Black offenders are also less likely to have their cases dismissed by a municipal judge and they are more likely to be taken into custody on outstanding warrants during traffic stops , compared to their white counterparts . The Justice Department plans to use the findings to negotiate policy changes with Ferguson officials and enter a consent decree , or to sue the city to force change . Brown was unarmed when he was shot multiple times by Wilson , . who told investigators he and Brown had an angry and violent . encounter , causing him to fear for his life when he shot Brown . A St. Louis County grand jury declined to indict Wilson , who . has since left the police department .
Family of killed black teenager Michael Brown plan to sue Darren Wilson and white police officer Ferguson , who shot him on August 9 , 2014 . Comes a day after Justice Department refused to prosecute over the death . A grand jury also refused to support charges against Wilson last year .