Racial discrimination is against the law. But that hasn’t stopped Attorney General Eric H. Holder Jr.’s Justice Department from bullying cities like Dayton, Ohio, and New York to implement racially discriminatory hiring practices for police officers and firefighters.

In 2009, the Supreme Court found that New Haven, Conn., racially discriminated against white and Hispanic firefighters when it invalidated the results of a promotional exam because no blacks had scored high enough to merit a promotion.

In Ricci v. DeStefano, there was no evidence that the exam was anything other than a fair and objective way to determine the most qualified candidates to keep the city safe. But, as Justice Samuel Anthony Alito Jr. noted, “city officials worked behind the scenes to sabotage the promotional examinations because they knew that, were the exams certified, the Mayor would incur the wrath of … influential members of New Haven’s African-American community.”

New Haven’s disreputable actions were an exercise in racial politics. Such “express, race-based decision making violates the law,” Justice Anthony M. Kennedy wrote for the majority.

But that doesn’t seem to be clear enough — or good enough — for Mr. Holder’s Justice Department. It wants Dayton and New York to exercise the same considerations that put New Haven on the wrong side of the law.

Dayton has written and oral entrance exams for police officer candidates. The tests are fully in accord with the Ricci decision. But the Justice Department is forcing Dayton to lower the passing grade because not enough black applicants are passing.

Dayton’s original eligibility criteria required candidates to score a D and a C on separate tests. The Justice Department is requiring Dayton to accept candidates who get an F on the second exam. Even candidates who fail to meet the most basic requirements can still get hired. That’s no way to build a “best and brightest” police force.

The Justice Department is making the same two claims New Haven made — and the Supreme Court rejected — in Ricci: 1. There is no need to use a written exam in recruiting police officers and 2. Dayton’s written exam has a “disparate impact.” (Fewer black applicants passed than whites.)

Police work requires quick thinking, superior judgment and excellent management skills. Dayton’s civil-service questions accurately assess these skills in an unbiased manner. Here’s a question from the exam that the Justice Department found to be discriminatory:

“As a police officer you will probably come into contact with a great number of citizens who are under emotional stress. If one of the citizens reacts to you in a resentful manner, your best approach would be to:

“A. Remind the citizen that his/her behavior will reflect unfavorably upon him or her

“B. Refuse to talk with the citizen until he/she cools down

“C. Respond as unemotionally and as objectively as possible

“D. Ignore the citizen’s comments and treat him/her forcefully”

The very idea that such questions discriminate on the basis of race is ludicrous. They address real situations that require officers to make appropriate judgment calls. In Ricci, the Supreme Court found such exams to be both job-related and consistent with business necessity.

Even Dayton Unit NAACP President Derrick L. Foward criticized the actions of the Justice Department. “The NAACP does not support individuals failing a test and then having the opportunity to be gainfully employed,” he said, adding, “If you lower the score for any group of people, you’re not getting the best people for the job.”

Such practical objections didn’t dissuade Justice from asking a federal district court to force the same race-based employment practices on the New York City Fire Department. U.S. District Judge Nicholas G. Garaufis, a Clinton administration appointee, complied. He ruled that because the percentage of black firefighters was not proportionate to the percentage of blacks in New York, the city is “discriminating” against black applicants and will have to alter its use of written exams.

With this ruling in hand, the Justice Department has effectively frozen FDNY’s hiring process. New York is appealing the decision, but the Justice Department is pressing harder. It recently asked Judge Garaufis to award damage payments and administer retroactive seniority and benefits to minority applicants, some of whom answered 70 percent of the questions incorrectly on FDNY’s firefighter exam.

In Ricci, Justice Alito wrote that “a public official cannot … engag[e] in intentional racial discrimination when making employment decisions.” Yet that’s what the Justice Department is forcing Dayton and New York to do. Moreover, its approach is calculated to ban local governments from applying even minimal standards of performance and ability in public-safety hiring.

By opposing basic performance standards designed to assure that people of all creeds and colors receive competent protective services, Mr. Holder’s Justice Department endangers public health and safety.

• Hans A. von Spakovsky is a senior legal fellow at the Heritage Foundation and a former counsel to the assistant attorney general for civil rights.