NEW YORK, Aug 22 (Reuters) - A group of 15 New York State voters has asked a judge to toss a case challenging the way prisoners are counted for redistricting purposes.

Earlier this month, Supreme Court Justice Eugene Devine allowed the voters to intervene as defendants in an action brought by upstate senators and some of their constituents. The suit sought to block a 2010 law that counts prisoners as residents of the community where they last lived, rather than where they are incarcerated.

The senators asked Justice Devine, of state Supreme Court in Albany, for a permanent injunction to prevent the New York State Legislative Task Force on Demographic Research and Reapportionment, or LATFOR, and the state Department of Correctional Services from acting on the law, known as Part XX.

On August 5, the senators moved for partial summary judgment, contending that the state constitution provides that the most recent federal census determines the population in any part of the state for apportionment purposes.

Last week, the 15 voters filed their own motion for summary judgment.

The prior method of counting prisons as residents of districts where they were incarcerated "unjustly inflated the political influence of districts with prisons," the motion said.

The corrections department moved to dismiss the case, arguing that Part XX "remedies the inequitable dilution of representation that resulted from the prior law."

LAFTOR did not file a motion in the case.

The case is Senator Elizabeth O'C. Little et al v. New York State Task Force on Demographic Research and Reapportionment et al, New York Supreme Court, Albany County, No. 2310-2011.

For the senators: David Lewis, Esq., and Steven Leventhal of Leventhal, Sliney & Mullaney.

For the voters: Brennan Center for Justice at New York University School of Law, the Center for Law & Social Justice, Demos, LatinoJustice PRLDEF, the NAACP Legal Defense and Educational Fund, the New York Civil Liberties Union and the Prison Policy Initiative.

For New York State Department of Correctional Services: Stephen Kerwin of the Attorney General of the State of New York.

(Reporting by Jennifer Golson)

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