In 2001, the state of New York passed a law aimed at helping drivers keep their eyes on the road and their hands on the wheel.
The state said drivers could use cell phones in transit if, and only if, they used a hands-free device to carry on the conversation. In the eight years since, four other states and the District of Columbia have followed suit.
But government documents released Tuesday suggest it doesn't matter whether commuters are holding their cell phones in hand or not: Data shows chatting while driving slows reaction time -- a finding consumer groups now say the government never stressed at the expense of people's lives.
After finally accessing the information, today Public Citizen and the Center for Auto Safety made public documents from the Transportation Department's National Highway Traffic Safety Administration, and charged that the government has not been upfront for six years about distractions caused by cell phones.
"What the government knew is that talking and driving is just as bad as drinking and driving," Clarence Ditlow, executive director of the Center for Auto Safety, told ABC News today.
"It doesn't matter whether it's handheld or hands-free," he added. "It's the distraction of talking to someone else, the conversation itself that causes the inattention that leads to crashes, deaths, and injuries."
Ditlow called the handling of those studies "a cover up," adding, "This is the worst case I've ever seen in the history of the Department of Transportation for failing to reveal a safety hazard."
But today Dr. Jeffrey Runge, NHTSA administrator at the time the studies were done, told ABC News they weren't trying to bury the data. He did concede they didn't mount a full force campaign to publicize the cell phone studies.
Runge said reducing the number of fatalities on the road by making SUVs safer, making sure people were wearing their seatbelts and reducing impaired driving took top priority instead.
"That's when we had 43,000 people dead," he recalled today. "I knew what my job was: To bring those numbers down."
Runge also said the issue of cell phone data was part of a "basket of emerging problems," but that there wasn't enough mature data yet to tackle the problem.
"The blowback of getting out in front without good data, I was concerned about that," he said.
Meantime, the government did warn that using a cell phone while driving can be dangerous.
On its Web site, NHTSA states that, "The safest course of action is to refrain from using a cell phone while driving."
As for whether it's safe to use a hands-free device, the NHTSA says, "The available research indicates that whether it is a hands-free or hand-held cell phone, the cognitive distraction is significant enough to degrade a driver's performance."
But it also states that research continues and that, "As we learn more about the impact of cell phone use on driver performance and crash risk, and as wireless technologies evolve and expand, NHTSA will make its findings public."
In two recent accidents on commuter trains, drivers were found to be using their cell phones moments before the crash.
More than 60 people were injured in Boston May 8 when a trolley crashed into another one shortly after the operator sent a text message to his girlfriend. In September 2008, 25 people died on a train in Southern California, including the operator, who sent 29 text messages on the day of the crash.
Studies have also revealed other hazards related to cell phone use -- whether due to kids using a phone in the crosswalk, people talking while ambling down the street, or teenagers texting while driving.
A total of 14 states and the District of Columbia specifically prohibit drivers from text messaging while on the road, according to the Insurance Institute for Highway Safety.
"Safety is the number one priority for the Department of Transportation and Secretary LaHood is deeply concerned that drivers are taking their focus off the road to send text messages or use their cell phone," countered Transportation Department press secretary Sasha Johnson in a statement today. "Distracted driving causes crashes and we want to stress that the best way to avoid accidents is for drivers to keep their eyes and their concentration on the road when they get behind the wheel."
Data from the government's 2003 document made public today specifically shows that there's a 38 percent increase of accident risk for cell phone users. It revealed that drivers made more the 200 million in-car calls each day at that time. It also revealed that 92.5 percent of cell phone drivers in crashes had prior traffic violations.
The document, marked "For Internal Use Only," says, "We recommend that drivers not use these devices when driving, except in an emergency."
It also said, "We are convinced that legislation forbidding the use of hand-held cell phones while driving may not be effective in improving highway safety since it will not address the problem…such legislation may erroneously imply that hands-free phones are safe to use while driving."
"This was the government's bible on cell phone use and cell phone research and it never got published," Ditlow said today.
"It was primarily a look at everything. It was a worldwide search of research on cell phone use and hazards."
Still, those findings weren't made public until now.
"We don't know whether the cell phone industry pressured the government to hide these studies or not," Ditlow said. "They clearly had an economic interest."
"At this point, the debate should not be about what the federal government didn't do," Anne McCartt, senior vice president for research at the Insurance Institute for Highway Safety, told ABC News today. "That's not the challenge, I think, in this area. The challenge is to come up with a counter measure, a program, a strategy that can reduce what we know is a dangerous problem and a problem that is becoming more and more common."
Today, the Center for Auto Safety is asking the Transportation Department to reconsider its petition calling for cell phones to be deactivated when the car starts. The safety center's petition was denied in June 2008.
"There's some technologies being developed that will try to either block signals allowing someone to talk on a phone or preventing telephone calls when a vehicle is moving," McCartt said. "Whether or not these will be effective and whether they'll be accepted by the public, I think is an unknown."
"It's a frustrating, unsatisfying answer, but we don't, at this point, know an effective strategy for getting drivers off their phones," she added.
The Center for Auto Safety tried to get access to NHTSA's studies on drivers' cell phone use in March 2008, but were denied the documents. The group filed a lawsuit with assistance from Public Citizen, which ultimately led to the information's release.
"It is a travesty that NHTSA kept secret factual information that could have saved lives," said Public Citizen attorney Margaret Kwoka in today's statement. "Although FOIA protects an agency's decision-making process, these documents reflect facts about safety risks that the public had every right to see."