A white officer has settled a federal lawsuit he filed against the city of St. Louis in which he claimed that police officials promoted a less-qualified black officer to lieutenant colonel.

Maj. Michael Caruso's lawsuit is the third the St. Louis Metropolitan Police Department has faced in five years over promotions. The lawsuits were filed by black and white officers. Two of the suits, including Caruso's, blame individual decision-makers for alleged discrimination. A third, filed in state court, claims that the process is unfair.

So how could the same process discriminate against both black and white candidates? The simple answer is that it relies on people to make decisions, said Donna Harper, a local attorney who specializes in workplace discrimination cases.

"You can have a great-looking policy in writing, but you have to rely on people to implement it," Harper said. "And when people implement, their own biases, their own interpretations can affect the outcome."

The fact that bias is invisible makes reform more difficult, said Brian Love, an attorney who represents three black officers who argue the promotions process makes it harder for officers of color to advance.

"People are not always conscious of bias existing in themselves," Love said. "And it's also hard to diagnose in someone else. It's a very difficult thing to say 'hey, I think my fellow officer may have a problem with being biased against certain groups of people.'"

The suits

Details of Caruso's settlement were not immediately available. He had accused the department of promoting Ronnie Robinson, who is black, to commander of the Bureau of Community Affairs even though Robinson did not meet the minimum job requirements.

In 2012, Sgt. David Bonenberger filed a similar federal lawsuit claiming the department denied him a leadership post at its training academy because they wanted to "bring color down to the academy." A jury later awarded Bonenberger $620,000, and the courts ordered the department to stop discriminating based on race.

Love's clients, who sued in state court, focus on the promotions process itself. All three officers applied for promotion to lieutenant in 2014, but were placed in lower "clusters," which made them less likely to advance to higher positions.

The people conducting the interviews were other officers from inside the department, some of whom had an "ax to grind," Love said. He said his clients also believe white officers received extra help with the tests.

The department does not comment on pending litigation.

Correction: An earlier version of this story misspelled the name of the employment law attorney quoted. Her name is Donna Harper, not Donna Harder.

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