Michael Brown's family file wrongful death lawsuit against Ferguson, Mo.

The parents of Michael Brown filed a wrongful-death lawsuit Thursday against the city of Ferguson over the fatal shooting of their son by a white police officer, a confrontation that sparked a national protest movement.

Attorneys for Brown's parents, Lesley McSpadden and Michael Brown Sr., filed the complaint at the St. Louis County Courthouse and called a news conference to announce the case, which had been expected for months.

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Messages seeking comment from Ferguson Mayor James Knowles III, city spokesman Jeff Small and an attorney for Darren Wilson, the officer who shot Brown, were not immediately returned.

Brown, 18, was unarmed and walking in the street with a friend on Aug. 9 when Wilson told them to move to the sidewalk. That led to a heated confrontation and a scuffle between Wilson and Brown inside Wilson's squad car.

Wilson shot Brown after the scuffle spilled into the street. Some witnesses said Brown was trying to surrender, but Wilson said Brown was moving toward him aggressively, forcing him to shoot.

Brown's shooting led to sometimes-violent protests and spawned a national U.S. "Black Lives Matter" movement calling for changes in how police deal with minorities. In the end, local and federal authorities ruled that the shooting was justified.

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A St. Louis County grand jury and the U.S. Justice Department declined to prosecute Wilson, who resigned in November. But the Justice Department released a scathing report citing racial bias and profiling in the Ferguson Police Department and a profit-driven municipal court system that frequently targets black residents.

Several city officials resigned following the review, including the city manager, police chief and municipal judge. The municipal court clerk was fired for racist emails.

Lower standard of proof

Civil cases generally require a lower standard of proof than criminal cases. Jurors must find a preponderance of evidence, not proof beyond a reasonable doubt needed to convict in a criminal trial.

Two decades ago, football star O.J. Simpson was acquitted of the killings of his ex-wife, Nicole Brown Simpson, and her friend, Ronald Goldman. But a civil jury awarded the Brown and Goldman families $33.5 million in wrongful-death damages.

The family of Amadou Diallo, an unarmed man killed by police in 1999, settled with New York City for $3 million in 2004 after filing a $60 million lawsuit. The city did not admit any wrongdoing. The settlement came after four officers indicted in his shooting were acquitted of second-degree murder and reckless endangerment.

Wrongful-death lawsuits have been filed in other recent high-profile cases, too.

In New York, the family of Eric Garner is seeking $75 million in damages. Garner, who was black and had asthma, died in July after a white plainclothes officer applied what a medical examiner determined was a chokehold after Garner was accused of selling loose, untaxed cigarettes on a city street.