A top federal highway safety official is warning Massachusetts residents not to drive “baked” as the state moves toward legal pot sales — stressing they “could die” or “kill someone else” by being stoned behind the wheel.

“People think they drive better when they’re driving high,” said Heidi King, deputy administrator at the National Highway Traffic Safety Administration, citing market research. “But we know that an impaired brain is not very good at judging whether it’s impaired.”

King approached the Herald to deliver her message to Massachusetts drivers at a MassDOT-sponsored forum on drugged driving in Boston yesterday.

“They get behind the wheel with confidence and they could get in an accident, they could die, they could kill someone else,” King said.

With legal pot sales just days away, King told the Herald it’s time to ramp up driver education.

The state needs to get the word out: “Don’t let a friend drive baked,” King said.

“We need to raise public awareness and strengthen the programs to keep our roads safe,” she said. “The most important thing is educating the public that many of the (pot) products that are coming out on the market are impairing.”

King credited the Herald’s extensive reporting on legalized pot for “getting the word out” on the dangers of driving while stoned. Herald reports have documented rising accident rates and fatalities in states that have legalized marijuana, the prospect of higher insurance rates and the difficulty of proving whether someone is legally impaired.

Jeff Larason, the state’s director of highway safety, echoed King’s concerns.

“What we’ve seen from Colorado and Washington, which are the first states that have legalized, there have been increases in the crashes and crash fatality rates involving cannabis in those states, so we’re concerned that we’re going to see the same kinds of things happen here in Massachusetts,” he said.

The MassDOT session touched on awareness, education and how to enforce the law.

Several law enforcement officials at the forum noted charging drug- impaired drivers will be a challenge.

“We have nothing that’s been provided to us like a Breathalyzer or something that would help us,” said New Hampshire Highway Safety Commander Cpt. Bill Haynes. “So, it’s very hard to prosecute.”

Under the Bay State’s pot law, a special commission on impaired driving must craft recommendations to keep drugged drivers off the road. That report is not expected to be delivered to the Legislature until January.

Meanwhile, there is no law that requires drivers suspected of being high to submit to a test — and there is no test in use.

For now, King said public awareness is vital: “We want everyone, just as they do with alcohol, to plan ahead.

“Plan a safe ride, plan a sober ride,” she added. “Similar to the campaigns we know from years ago in alcohol, don’t let a friend drive high.”