The firm matched names with addresses in both files and added dates of birth to voter lists. Then it sold the information to several Wisconsin campaign consultants, WISC-TV reported.
The firm's request form to the DOT said it's authorized for use in research activities, as long as personal information is not published, re-disclosed or used to contact individuals.
"If you're mailing to voters, you don't just want to mail to everybody who's a voter. You want to mail to people for whom some issue is important or who are likely to vote in a given election or whatever," Grebner said.
The DOT said it only complies with the federal laws, deferring to the U.S. Department of Justice, which enforces the Driver Privacy Protection Act.
"We don't take a position on anyone's use on the records we provide," Smith said. "That enforcement process is for the Department of Justice."
John Vaudreuil, U.S. attorney for Wisconsin's western district, said his office has only received one complaint about five years ago that "didn't amount to much."
"We've never actually prosecuted or gone to the next level with anything like this," Vaudreuil said. "It may very well be that it's such an age of your addresses are everywhere, you get mailings of every solicitation in the world; you read them or don't read them, and it just may be people aren't that concerned. I don't really know."
Social Security numbers are kept private and are not shared with requests submitted under the Drivers Privacy Protection Act or law enforcement.
Current law requires the DMV to provide Social Security numbers to the Department of Workforce Development if someone has not paid child support and the Department of Revenue for unpaid taxes. In rare instances, a court may order the DMV to provide the Social Security number for a court proceeding and the federal government is authorized access to Social Security numbers under commercial driver license (CDL) guidelines.
Under the Drivers Privacy Protection Act, date of birth is not considered personal information and therefore is not protected.
Grebner said he doesn't think he violated the law. He said, either way, he didn't find the driver record file useful so he probably won't buy it again.
The state of Wisconsin is making millions off of selling a second list with drivers' personal information, WISC-TV reported.
The department makes more money and has more requests for full driving records. These contain the same information as the driver record file plus information on traffic crashes, tickets and withdrawals like revocation or suspensions.
While the driver record file costs $250, full driving records cost between $5 and $7 per driver record.
In 2010, the DOT made more than $16 million selling full driving records, WISC-TV reported.
Explore Information Services buys full driving records each month.
"We provide specific information about specific individuals that they insure so they can establish the rates for that particular driver," said Michael John, a company spokesman, in a phone interview.
Explore Information Services has a contract with the DOT and a monthly bill of approximately $170,000.
But Explore doesn?t have the largest contract with the DOT. That belongs to LexisNexis.
The department said, "LexisNexis works with insurance agents for six month policy updates and immediate insurance quotes."
This could potentially be the reason drivers are able to call an insurance company for a quote and be provided one quickly.
The DOT said that LexisNexis pays the department $874,618 every month.
While most purchasers of both files are vehicle insurance consulting and marketing firms, no state or federal agency can say if the mailings people get originated from information purchased through the DOT.
In place in Wisconsin since 2000, the Driver Privacy Protection Act only goes as far as Wisconsin motorists allow.
"And to me, that's sort of the lesson from (this), is to read what we sign and make a decision," said Vaudreuil.