(CNN) The Justice Department sued Baltimore County, Maryland, and its police department last week, accusing them of discriminating against black applicants for entry-level police jobs -- a rare step in making an allegation of systemic misconduct by law enforcement under the Trump administration.

The lawsuit alleges a violation of Title VII of the Civil Rights Act of 1964, which prohibits discrimination against employees or applicants based on race, among other things. It appears to be one of the only examples of a so-called pattern-or-practice lawsuit -- a full-scale civil rights inquiry into policing practice -- filed under the President Donald Trump -led Department of Justice against a police agency. While the type of investigation was used throughout the Obama administration, in line with a national reckoning over officer-involved shootings, the Justice Department in recent years has largely avoided the practice as they've shifted tone to one that embraces rank and file police and prioritizes morale over sweeping reform efforts.

According to the lawsuit, the police force, which covers a largely suburban area outside the city of Baltimore, used a written exam to test for things like reading comprehension and "interpretation of data," and black applicants failed at a statistically significant higher rate than white applicants.

"As a result of its use of these written examinations, Baltimore County has hired fewer African American applicants as BCPD entry-level police officers and police cadets since January 1, 2013 than it would have had it used a non-discriminatory screening device," the lawsuit contends.

The Justice Department has continued to bring cases against police officers for specific allegations of misconduct, like excessive force, although Trump's first attorney general, Jeff Sessions, sharply limited the use of consent decrees, a court-enforced agreement that federal officials had entered into with a law enforcement agency to remedy bad behavior.

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