A day after publishing a scathing report on Puerto Rico's police department, the American Civil Liberties Union hit the PRPD with a federal lawsuit accusing officers of using excessive force and violating civil rights during demonstrations organized by university students and public employees.

The lawsuit, filed Wednesday, alleges that Superintendent Hector Pesquera has encouraged a pattern of violence against demonstrators. It seeks an injunction to force the department to create a policy on how to handle demonstrations and use of force, and to establish a system that makes it easier to file complaints and for authorities to document alleged excessive use of force.

The police department has pledged to make reforms and adopt measures recommended in a scathing report issued by federal prosecutors last year that accused police of corruption, illegal killings and civil rights violations. The new suit aims to make certain reforms mandatory.

"We are not willing to simply accept expressions of goodwill," said Marjorie Lindblom, an attorney with New York-based law firm Kirkland & Ellis LLP, which filed the suit with the ACLU.

If you are going to protest, you are going to be beaten, you are going to be persecuted, you are going to be arrested.

- Ramon Vargas, President of the University Student Council

Pesquera took over in April, long after the incidents that prompted the suit. Lindblom said he was named because he would be responsible for overseeing the changes the plaintiffs demand.

He said in a telephone interview that the department already has developed a use-of-force policy approved by federal justice officials. He said 15,000 of the department's 17,000 officers, which is the second-largest U.S. police force, have already been trained under the new policy.

Pesquera, who previously served as director of the FBI office based in Puerto Rico, said he also has appointed a 33-member committee to analyze and implement the federal Justice Department's recommendations.

"I've been here for two months and we have taken extremely aggressive steps to reform the police," he said. "We have made a commitment ... We are not going to violate anyone's civil rights."

The lawsuit is on behalf of the Central Federation of Workers and the student council of the University of Puerto Rico's Rio Piedras campus. It states that the alleged abuses began in 2009 during protests over government layoffs and university cutbacks.

"There was a purpose behind the police abuse, behind the beatings," said Ramon Vargas, president of the university student council. "If you are going to protest, you are going to be beaten, you are going to be persecuted, you are going to be arrested."

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