PHOENIX — Saying he’s just following the law, Attorney General Tom Horne refused Monday to drop his lawsuit against community colleges that offer lower in-state tuition to students who qualify for the federal Deferred Action for Childhood Arrivals program.

Horne told a group of activists who met with him he is bound by a 2006 voter-approved proposition that says those who are not citizens or legal residents are not entitled to “resident’’ tuition, regardless of how long they have lived in the state.

Horne would not answer questions on how he feels about the law, saying his views are irrelevant.

“My job is to enforce the law as it is written,’’ he told the nearly dozen people invited for the meeting.

Horne’s office sued the Maricopa Community College District after its board adopted a policy saying those in the DACA program are entitled to the lower tuition. He said he will pursue other colleges that have adopted similar policies, including Pima Community College.

The meeting turned ugly at several points, with some participants telling Horne he has no moral right to decide the issue, citing a series of Horne’s legal problems, including a bump-and-run accident to which he pleaded no contest earlier this year and a finding by Yavapai County Attorney Shelia Polk that he violated campaign finance laws, a contention he disputes.

One attendee was arrested and charged with trespass for refusing to leave the office in protest of Horne’s refusal to reverse his position.

Besides limiting resident tuition to citizens and legal residents, the 2006 initiative mandates higher tuition must be charged to those who are “without lawful immigration status,’’ and denies any form of financial help “that is subsidized or paid in whole or in part with state monies.’’

The DACA program, approved last year by the Obama administration, is available to those who arrived in this country as children but are not here legally. It allows them to remain and get work permits. At last count more than 20,000 applications had been received from Arizona residents, with close to 17,000 approved.

But Assistant Attorney General Leslie Cooper, who is pursuing the case against Maricopa Community College, said that’s not the same as “lawful status.’’

“A number of different groups of people are entitled to stay here and work, even though their status isn’t lawful,’’ she said.