BOSTON

A lawsuit challenging the state’s 20-day voter registration cutoff deadline is working its way through the courts with a goal of finding a final resolution ahead of next year’s elections.

Defenders of the 20-day cutoff say it’s an important tool for the orderly management of the election process in Massachusetts.

Critics say ending the voter registration period 20 days before Election Day is arbitrary. They point to the state’s adoption of early voting last year that allowed voters to begin casting ballots on Oct. 24, just five days after the Oct. 19 registration cutoff.

“So as a practical matter you had to be able to let people vote five days after the registration cutoff,” said Kirsten Mayer, a lawyer with the firm Ropes & Gray arguing against the existing registration deadline. “So under those circumstances how can you say you need 20 days?”

The case began after three voters who failed to register by last year’s deadline went to court for the right to cast a ballot. They were ultimately allowed to vote, but the larger issue of the 20-day cutoff is continuing to move through the courts.

Mayer and lawyers from the American Civil Liberties Union of Massachusetts are pressing the case on behalf of the thousands of voters they say are denied an opportunity to cast a ballot because they fail to register in time.

A spokesman for Secretary of the Commonwealth William Galvin, who oversees the state’s elections, declined to comment, citing the ongoing lawsuit.