A new law designed to help police keep closer tabs on criminals on probation and parole may have less teeth than advertised, exempting thousands of offenders from scrutiny.

When lawmakers passed the Reduction of Recidivism Act last month, it was touted as a get-tough measure that would allow police to search some 31,000 criminals on probation and parole without a warrant. The problem, some officials said, is it doesn't do that.

The law requires criminals to sign forms consenting to searches before they are released to community supervision. It does not, however, say anything about the thousands of folks already on probation April 28, when the measure was enacted.

Probation officials can ask those offenders to sign the waiver, but it does not appear they are under any legal obligation to do so. Without that written consent, police are not authorized to search those people unless they have a warrant, the state Department of Probation, Parole and Pardon Services stressed in a May 4 advisory to law enforcement.

Though the law went into effect the day it was passed, the probation department still is trying to work out the details of how it will be applied on the street. Among other things, the agency is working to create a database police can check from the road, at all hours, to verify that a criminal is on community supervision and has consented to be searched, said Pete O'Boyle, the department's director of public information.

The agency has set a target date of July 1 for the system to be in place so police can begin conducting the warrantless searches, O'Boyle said.

The probation department hasn't taken an official position on whether the new law authorizes warrantless searches of offenders already on community supervision when the law took effect. The law appears to contain language that would retroactively make current parolees subject to the searches but not probationers, who make up the overwhelming majority of criminals on supervised released.

Senate President Pro Tem Glenn McConnell, R-Charleston, said that the bill would have had constitutional issues if lawmakers had tried to make it retroactive. "You've got to have a starting point," he said. "The great thing about this law is, it's a great start."

Miller Shealy, a professor at the Charleston School of Law and a former prosecutor, said time on probation and parole is considered part of an offender's sentence in a criminal case. Changing the terms of that sentence after the fact likely would violate that person's right to due process, he said.

It would be akin to lumping five more years onto an already imprisoned burglar's sentence because the Legislature decided to increase the maximum penalty for that crime at a later date, Shealy said.

Jeff Moore, executive director of the South Carolina Sheriff's Association, said he has advised county sheriff's offices to hold off on warrantless searches until the probation department works out these issues, comes up with guidelines and develops a database to help deputies figure out who can be searched and who is off limits. "I think you're looking at civil liability, otherwise," he said.

Charleston Police Chief Greg Mullen was a leading proponent of the measure and traveled to Columbia to fight for its passage. He declined to comment Monday on the confusion over its implementation, saying through a spokesman that he wanted to give probation officials time to develop a workable process.

Eventually, all offenders on probation and parole will be brought under the search requirements, but that could take years as current criminals cycle out of supervision and new ones come in.

Between 7,000 and 8,000 criminals enter community supervision each year, O'Boyle said. The state has a five-year limit on probation terms. For some, parole can be in place for life, but many others cycle out of supervision in a matter of years, he said.

McConnell said the law will been a boon to public safety efforts as more and more criminals become subject to the possibility of being searched by police. "It will, over the years, have an increasingly positive effect," he said. "We had to start somewhere."

Yvonne Wenger contributed to this story.