Authorities here and elsewhere in the nation are investigating allegations that thousands of fake names have been submitted on voter registration forms.

While such activity is a crime, experts say there is little or no threat to the integrity of the upcoming election, because newly registered voters are required to show identification at the polling place.

Investigators here and elsewhere are focusing on voter registration campaigns conducted by the Association of Community Organizations for Reform Now, known as ACORN.

Maryellen Hayden, head organizer of the Allegheny County branch of ACORN, which has a long involvement in voter registration drives, said she is not surprised by the fraud allegations.

"There is nothing easy about voter registration," she said yesterday after the district attorney and police officials revealed they are investigating whether some ACORN staff members committed perjury and fraud by knowingly submitting fake names on voter registration forms to the county Elections Division.

It is difficult for voter registration operations to fully protect themselves against fraud by some of their employees or volunteers, because of the nature of the work they do, Ms. Hayden said.

"We hire people directly from the communities we serve, and we at ACORN pay them $8 an hour and ask them to collect between 15 and 20 signed voter registration cards in five hours," she said.

The problem arises "when you have some lazy people who might choose to sit at a McDonald's and fill out the forms themselves instead of hitting the pavement and collecting good registration signatures from people," Ms. Hayden said.

The FBI and law enforcement agencies in New Mexico, Nevada, Missouri, Indiana, Michigan, Ohio, Wisconsin and Pennsylvania are looking into thousands of voter registration forms submitted by ACORN during this year's primary and presidential election seasons.

Allegheny County District Attorney Stephen A. Zappala Jr. and county police Superintendent Charles Moffatt yesterday said they are investigating and considering charges against ACORN staffers and other voter registration groups.

"It's not just ACORN. There are other groups, too. We are looking into all these cases because forgery is a crime," said Mr. Zappala.

"We have done our investigation, and we are now talking to the district attorney on whether we have enough to bring charges," said Superintendent Moffatt, who did not specify the number of registration forms his office reviewed.

Mark Wolosik, head of the county elections division, could not specify a number of fake registration forms either, but said he referred "less than 100" to county police in the last few weeks.

There is no likelihood that this type of fraud could influence the outcome of an election, Mr. Wolosik said, because every new registered voter must to show photo ID or an approved form of non-photo ID.

The real victims are the voter registration groups like ACORN, said Ms. Hayden.

"We are the ones who pay these people our hard-earned money and we don't like to waste it on the collection of fake signatures," she said. "Let the officials tell us who faked the forms and we will testify against them."

Ms. Hayden said some groups politically opposed to ACORN have seized on the issue in attempts to "suppress and intimidate voter registration efforts in the future."

"We already have a system that sorts out the good registration cards from the bad ones," she said. "When our staffers bring back registrations from the field, we double-check them by calling back the people they registered.

"We then sort out the forms in piles of verified registration forms, ones where we could not get someone on the phone and the ones we think are fake or have significant problems," Ms. Hayden said.

"We get all those forms and send them into the elections office, but we tell them about the pile of forms we think have problems. And now they are using our own system against us," she said.