Attorney General Eric Holder talks with Capt. Ron Johnson of the Missouri State Highway Patrol in Florrissant, Mo., on Aug. 20. The federal investigation into the Ferguson Police Department that resulted from the shooting of Michael Brown is on going. (Pablo Martinez Monsivais/AP)

The Justice Department still has two opportunities to bring criminal charges and overhaul the Ferguson Police Department in the case that grew from the fatal police shooting of Michael Brown.

In September, Attorney General Eric H. Holder Jr. launched a federal investigation of the Missouri city’s police force to examine whether officers routinely engaged in racial profiling or showed a pattern of excessive force. Investigators from Justice’s Civil Rights Division are reviewing the training officers receive on racial profiling and the use of force, including deadly force.

The Civil Rights Division is conducting a separate investigation of the Aug. 9 shooting of Brown, who was unarmed, to determine whether there is a civil rights case to be brought against Officer Darren Wilson, whose fatal shooting of Brown sparked months of protests.

Holder urged protesters in Ferguson last week to avoid violence in response to a St. Louis County grand jury’s report on its investigation of the shooting. Justice officials also privately reached out to Missouri Gov. Jay Nixon (D) to express Holder’s displeasure and “frustration” that Nixon declared a state of emergency and activated the National Guard in advance of the grand jury’s findings.

The Justice Department’s broad investigation of the policing practices of the Ferguson Police Department could result in wholesale reforms and reorganization of the force, according to Justice Department officials.

The probe, which could take months to complete, follows a process that Civil Rights Division attorneys have used in investigations of 20 other police departments across the country. The Justice Department is also conducting a review of racial profiling and other practices by the St. Louis County Police Department, which voluntarily agreed to the review.

At a news conference announcing the investigation, Holder said that “anecdotal accounts underscore the history of mistrust of law enforcement in Ferguson.”

The department’s investigation of Wilson appears to be less likely to lead to federal charges. Investigators have said that the evidence at this point is not strong enough to bring criminal civil rights charges against Wilson.

As in similar cases, federal law sets a high bar for bringing civil rights charges against a police officer. Federal prosecutors must prove beyond a reasonable doubt that the officer intended to violate a victim’s constitutional rights.

The investigation of Wilson is being conducted under a federal statute that makes it a crime for a person with government authority, which is legally referred to as “acting under the color of law,” to “willfully” deprive a person of a right or privilege protected by the Constitution or federal law.

Civil rights investigations can drag on for years. The Justice Department’s civil rights investigation into George Zimmerman, the neighborhood watch volunteer who fatally shot unarmed 17-year-old Trayvon Martin in Sanford, Fla., is still active after two years, although law enforcement officials have said privately that there is not enough evidence to bring federal charges.

But Holder — who announced in September that he is stepping down as attorney general — said he will release the results of the Wilson investigation before he leaves office. President Obama has nominated Loretta Lynch, the U.S. attorney for the Eastern District of New York, to succeed Holder, and Holder said he will remain as attorney general until a nominee is confirmed.

A grand jury has declined to indict Ferguson, Mo. police officer Darren Wilson in the shooting death of 18-year-old Michael Brown. Here is a look back at the events following the August shooting. (Gillian Brockell and Sarah Parnass/The Washington Post)