The Justice Department will not bring any federal civil rights charges against Darren Wilson, a white police officer who was involved in the shooting death of an unarmed black teenager in Ferguson, Mo., last year.

Federal prosecutors are drafting a legal memorandum for Attorney General Eric Holder to essentially close the case, which might spark another wave of heated protests and riots similar to those that followed last year's refusal of a St. Louis County grand jury to bring charges for homicide or any other state crime against Wilson, The New York Times reported Wednesday, citing unnamed law enforcement officials.

Last July, Wilson shot and killed 18-year-old Michael Brown after a confrontation in the small, mainly black community near St. Louis. If the case is closed, Wilson will not face charges for violating Brown's civil rights.

The 18-year-old victim's family will "wait for official word from the Justice Department" before commenting. "The family won't address speculation from anonymous sources," Benjamin Crump, a lawyer for the Brown family, said in a statement.

Although an FBI investigation failed to find any evidence to support charges that Wilson had willfully intended to violate Brown's rights when he opened fire on him, a federal civil rights investigation still remains open into whether Ferguson police engaged in discriminatory traffic stops and used excessive force, officials said.

However Wilson, who later resigned from the Ferguson Police Department, has maintained that after he asked Brown and a friend to move off a street to a sidewalk, Brown punched him, reached for his gun during a struggle, then charged him, causing Wilson to fatally shoot Brown in self-defense, according to New York Daily News.

"DOJ has known from the very beginning that no violation of civil rights occurred when Officer Darren Wilson shot an aggressor, Michael Brown, in self-defense. Instead of deliberating immediately and issuing their conclusion in the fall, the Obama Administration let the embers of civil unrest burn, fanned by the rhetoric of opportunistic race dividers," said Ron Hosko, president of the Law Enforcement Legal Defense Fund.

Following the grand jury's decision in November, many civil rights advocates were hoping that the Justice Department would file federal charges against Wilson - similar to how the department brought civil rights charges, and obtained two convictions, after four Los Angeles police officers were acquitted in the Rodney King beating, The Washington Times reported.

But having to prove the "intentional" nature of an act "made it virtually inconceivable that there would be a criminal federal indictment given the conflicting nature of the evidence," a high-ranking Justice official in a previous administration said.

Over the span of Holder's tenure, the Justice Department has launched 20 civil rights investigations against local police departments across the United States, including a probe of the Ferguson police department.

Meanwhile, the Justice Department declined to make comments about the ongoing investigation on Wednesday, Voice of America reported.