Too bad it took the U.S. Justice Department to say what the Philadelphia School District tried to downplay after Asian students were attacked last year.

A Justice Department investigation found the district deprived Asian students at South Philadelphia High School of equal protection "by remaining deliberately indifferent to known instances of severe and pervasive student-on-student harassment of Asian students based on their race, color, and/or national origin."

That is a stinging rebuke to the district for its not responding adequately to the mounting unrest at the school, and at others with immigrant students.

West African students have been similarly preyed upon by bullies. And a brawl Wednesday at Frankford High involving as many as 50 students is a reminder that school violence in general remains a persistent problem.

Going forward, the district agreed to a federal consent decree with strict guidelines to protect students from racial bias. But in its consent, the district still denied findings by federal investigators that it essentially ignored the harassment of Asian students.

South Philadelphia High exploded with violence Dec. 3, 2009, when 30 Asian students were attacked during a daylong series of assaults carried out by mostly African American students.

Student leader Wei Chen was among the "heroes" singled out by federal investigators. Chen, who graduated last spring, has worked with the school's new principal, Otis Hackney.

By most accounts, the climate at the school has improved this year. The district has already made some changes called for in the agreement.

The Justice Department's findings should bring a measure of comfort to Asian students and their parents. Their complaints were long ignored by the district, allowing the problem to fester.

Besides guidelines to protect students from bullying and harassment, the district agreed to submit to federal and state oversight through June 2013.

The district has 30 days to file a plan with the court on how it intends to carry out the settlement. Executing the plan will be the key, as well as close monitoring to ensure compliance.

Those are good steps, but the efforts should not stop there. The district should take the same vigilant approach to ending violence at other schools.

The agreement includes provisions that can be used to protect students of all races across the district. They include language on handling racial harassment complaints, translation services for immigrants, and required annual staff training.

Superintendent Arlene C. Ackerman said the consent decree recognizes the lessons learned. Let's hope so. No students should ever have to go to school in fear, knowing that the adults in charge are looking the other way when they are in danger.