PHOENIX - The Arizona Students' Association is asking a federal judge to void a vote by the Board of Regents changing how its fees are collected, claiming it was retaliatory.

The lawsuit says students have voted twice to allow the fees. While the fees are collected automatically as part of tuition, students can request a refund.

The regents voted in November to suspend the fee, then voted this month to allow the fee again starting with the fall semester - but only on an "opt-in" basis.

The policy also requires the association to reimburse the universities for any administrative costs of collecting the fees.

Attorney Stephen Montoya says both actions are in retaliation for the association's advocacy last year of Proposition 204.

That measure, which voters turned down, would have imposed a permanent 1-cent sales tax, with the proceeds largely earmarked to fund education, including some money for the universities and financial aid. It was opposed by Gov. Jan Brewer, who appointed most of the Board of Regents' voting members.

Montoya is asking the federal court to rule the regents' action violates the student association's constitutional free-speech rights, "causing a chilling effect on ASA's political speech" and depriving it of its only source of income.

Regents' spokeswoman Sarah Harper said the change came after students raised concerns over several years. She said the change does not eliminate the $2-a-semester fee, but leaves it to ASA to decide how to get students to contribute "outside of public university collections processes." The fee generated more than $580,000 in 2010-2011.