AUGUSTA, Maine — More than two dozen Maine residents who are challenging the legality of the state’s sex offender registry are now speaking with one collective, determined voice.

At least 25 cases brought by “John Does,” anonymous sex offenders whose names are now on the registry, seek to have their names removed from the public list because they were added long after their original sentences had been served. The cases have been consolidated into one collective lawsuit in Kennebec County Superior Court before Judge Michaela Murphy.

While it could be months before Murphy decides the fate of these offenders, defense attorneys predict the number of cases could continue to grow rapidly.

“The people that have filed so far are primarily people with money to spend, but there are many others who don’t have a penny to devote to this,” said Bangor lawyer Stephen Smith, who is in the process of adding two John Does to the list. “If there is any success from the defense, I think you’ll see a big secondary flood of cases.”

Jim Mitchell, an Augusta attorney who brought the first John Doe case to court in 2006 and now represents 14 clients, is not surprised that so many are coming forward.

“My goal is to get my clients removed from the registry, but if in doing so we get the law declared unconstitutional, so much the better,” he said.

When the state Legislature amended Maine’s sex offender registry three years ago, it added hundreds of new offenders to an already substantial list. The change required those who had been convicted of sex crimes between 1982 and 1992 to register as sex offenders.

Many offenders did so without objection, but others contended they were being punished retroactively for crimes whose sentences had already been served.

According to defense attorneys, some John Does say their new sex offender status has cost them jobs or has resulted in evictions from apartments. Some say they have endured shame and stigma from family, friends and co-workers for crimes long forgotten. Some have lost pieces of the support system that is crucial to their rehabilitation. Zachary Heiden, an attorney with the Maine Civil Liberties Union, is watching the cases closely.

“There is much more danger of people concealing their identity when there are harsh punitive registration requirements,” Heiden said in a recent interview. “Offenders often are unable to get a job or find a place to live, and ultimately they have no choice but to assume a new identity.”

The first John Doe lawsuit was filed in 2006 after a man was ordered to submit his name to the state’s sex offender registry for a crime he committed as a teenager in the 1980s. His notice came about one week before a young Canadian man stalked and killed two Mainers whose names and addresses he found on the state’s online sex offender registry.

The John Doe, concerned about his safety, asserted that his rights were being violated because Maine’s Sex Offender Registration and Notification Act didn’t even exist when he was convicted.

That case initially was dismissed in Kennebec County Superior Court. However, it eventually made it to the Maine Supreme Judicial Court where the lawsuit was reinstated, a decision that helped pave the way for many others to file similar suits.

The central question in the John Doe cases is whether requiring offenders who committed crimes between 1982 and 1992 to register is a punitive action or a preventive measure essential to protecting the public. In the Law Court decision that reinstated the first John Doe case, one justice compared the retroactive penalties to “the shaming and ridicule penalties of colonial times.” He also warned that it could encourage retribution and vigilante violence. Nowhere was that more evident than the murders of William Elliott, 24, of Corinth and Joseph Gray, 57, of Milo in April 2006.

Deputy Attorney General Paul Stern, who is representing the state in the John Doe cases, did not return a call last week for comment. However, in recent court filings, Stern warned that allowing offenders who committed crimes before 1992 to live in anonymity could be a damning decision.

“If the Maine courts decide to enjoin the operation of the registry or the Internet posting of registrants, then Maine will stand alone in the entire country, making Maine the refuge for countless sex offenders who wish to conceal their criminal pasts from neighbors, landlords, employers and potential future victims,” Stern wrote.

Smith, who has represented sex offenders in criminal and civil matters on numerous occasions, said the registry changes disrupted the lives of many people in an irreversible way. Some offenders, he said, are violent sexual criminals or serial child molesters who pose an obvious threat but many are not.

As these John Doe cases slowly move forward through the court process, state lawmakers again are preparing to revisit Maine’s sex offender laws and consider changes that could help address many of the offenders’ concerns.

The Criminal Justice and Public Safety Committee will hold an all-day meeting Sept. 29 in Augusta to hear from experts in other states that have made changes to sex offender registries. The session will precede the committee’s work to craft legislation that would, among other things, create a tiered system. If successful, some offenders would have to submit their names only to a “silent” registry available to public safety officials.

But Mitchell, who watched earlier this year as Gov. John Baldacci vetoed a bill that would have changed the registry and helped some of his clients, said he’s through waiting for lawmakers.

“If they want to do something, more power to them, but we’re not listening any more,” he said.

Smith added that he’s not convinced state legislators are committed to making changes.

“It might be a good way to resolve this, but frankly, I don’t have a sense of how much political pressure is being placed on this,” Smith said. “It’s just not that popular.”

Heiden said he thinks the collective John Doe cases could be a landmark for civil rights.

“This is a big undertaking and lawyers want to be careful,” he said. “But the advantage of a case like this is that it’s going to get so much attention. And if it improves the law, it could benefit everyone, not just these few.”