PROVIDENCE, R.I. — Rhode Island police departments that require officers to issue a certain number of traffic tickets are breaking a state law and should stop, civil liberties advocates said in a letter to Rhode Island police chiefs, which was released on Tuesday.

The state chapter of the American Civil Liberties Union said it sent the letter last week following reports by WJAR-TV of officers being mandated to make a certain number of stops within a certain timeframe and not to give warnings.

The letter from ACLU Executive Director Steven Brown cited a state law enacted in 2010 that specifically prohibits ticket quotas. He said quotas send a message that police enforcement is more about making money than enforcing the law fairly.

“An encounter between a motorist and a police officer over a traffic violation is never a pleasant one, but it is even less so when the basis for the stop is to meet a quota, not to address a truly legitimate safety need,” Brown wrote.

He said in a news release that the ACLU is considering legal action.