BOSTON — Massachusetts public schools punish a disproportionately high number of minorities and students with disabilities with out-of-school suspensions, putting them at higher risk of dropping out or getting in trouble with the law, according to a civil rights group.

About two-thirds of those suspensions are for minor infractions, including nonviolent, noncriminal and nondrug offenses, according to the report released Tuesday by the Lawyers’ Committee for Civil Rights and Economic Justice.

Black students received 43 percent of all out-of-school suspensions and 39 percent of expulsions despite making up less than 9 percent of students enrolled. Black students were almost four times as likely as their white peers to be suspended. Latino students were about three times more likely than white peers to be suspended.

Students with disabilities were suspended from school at a rate three times that of their peers. “If out-of-school suspension predicts dropout, why are we using it to address minor misbehavior?” co-author Matt Cregor said.

The report was based on disciplinary data from the 2012-13 school year released by the state Department of Elementary and Secondary Education. Massachusetts’ public school students lost at least 200,000 days in the classroom to discipline during the year.

“The Department is aware of the data cited in the report, and we are aware of high suspension rates at some charter schools. We began having discussions about the data before the report was released, and we urge people not to look at it in isolation,” said Jacqueline Reis, a spokeswoman for the education department.

“Other factors such as attrition rates, whether the same students are suspended more than once and the length of suspensions are also important pieces to consider,” she said.

A message left for the Massachusetts Secondary School Administrators’ Association was not immediately returned.

The study also found that charter schools are more likely to punish students than traditional public schools. One Boston charter school disciplined nearly 60 percent of its students with out-of-school suspensions. “Given the extra steps parents take to enroll their children in charter schools, parents should not have to fear their children will be pushed out of them,” Cregor said.

The state’s overall out-of-school suspension rate was 4.3 percent, below the national average, but many urban districts had much higher rates, including 21.5 percent in Holyoke. Fall River, Lynn, Brockton, Springfield and Worcester systems were all higher than 10 percent.

“Suspension rates as high as these should make us question whether we are meeting the needs of the students in our schools,” said Joanna Taylor, the report’s lead author.