If you get convicted of aggravated or subsequent DWI, you won't get your license back until you have an ignition interlock installed on any vehicle you plan to drive.

A new law that took effect in July mandates the breathalyzer-type devices for all but first-time offenders.

Previously, New Hampshire law mandated ignition interlocks only for those convicted of driving after their licenses were revoked for DWI; it gave judges discretion in ordering the devices for other offenders.

But that wasn't working, according to Sen. Robert Clegg, R-Hudson.

Clegg serves on the Senate Judiciary Committee, which added the new interlock provisions to a House bill near the end of this past legislative session.

Clegg said judges were not ordering the devices for repeat offenders because the interlock law didn't make it mandatory. "So we beefed it up," he said.

"If you have an alcohol problem, you don't belong behind the wheel. If you can't stop doing it, the interlock is the best way to keep them off the road."

The original law creating an ignition interlock program in New Hampshire dates back to 2000, but the program never got off the ground. It took until last year for the state to enact administrative rules and approve contracts with two vendors to supply and service the court-ordered devices.

Craig Champagne is the service facility manager for New Hampshire for Draeger Safety Diagnostics, one of the two state-approved interlock companies. With the passage of this summer's tougher law, Champagne said, he's been bracing himself for a wave of requests for the devices.

But he may have to wait a bit longer.

Edwin Kelly, administrative judge of the District Court, noted a conviction for aggravated DWI carries a minimum one-year license revocation; the revocation period is at least three years for a subsequent DWI conviction. The way the law is written, a convicted driver only has to get the ignition interlock when he wants his license back.

"It could be quite a ways down the road before we start seeing the use of it," Kelly said.

Tom Hettinger, administrator for the Division of Motor Vehicles, said the DMV has been notified of 51 ignition interlocks ordered by the courts, but he knows of only one person who actually has had the device installed so far.

The new law also increases the mandatory period for an interlock in aggravated and subsequent DWI cases to a year, while the maximum remains at two years. And it authorizes the DMV to mark a convicted driver's license and license plates to indicate an ignition interlock has been ordered.

An ignition interlock requires a driver to pass a breath test before starting the vehicle and at random intervals during the trip. If you fail the initial test, the car won't start; if you fail one of the "rolling retests," the car's horns and lights are activated until you pull over. The car then won't restart for 12 hours, and you'll have two days to contact the vendor and pay a fine before the car won't start at all, according to Champagne.

It costs a driver $60 for installation, and $60 a month to lease the device, he said.

The new law, Kelly said, "certainly sends a strong message to people that New Hampshire is very serious about this."

"And for those people who are law-abiding, but have an alcohol problem, it's going to keep them from driving, so it will have a positive effect."

A 30-year-old mother from a small town in southern New Hampshire told the New Hampshire Sunday News that having the ignition interlock on her car for the past 18 months has been a "blessing."

Ordered by a Massachusetts court after her second DWI conviction within four years, the interlock is a "daily reminder in my circumstances that I can't drink," said the woman, who asked her name not be published.

But she looks forward to the day it can be removed, she said. Her 2-year-old daughter recently began imitating her mother by blowing into the interlock handset whenever she gets in the car.

"It bothers me," the mother said. "I'm paying a price for something and I'm seeing the effect on her."

In some states, drivers must travel to vendor locations every month to have their ignition interlocks checked. For New Hampshire residents, Champagne has a mobile van so he can travel to his customers' homes.

"It takes about 15 minutes to calibrate the unit, and download the information out of the interlock," he said.

Judge Kelly said there could be other avenues to use the ignition interlock program -- as an incentive for some drivers to get their licenses back earlier if they successfully complete alcohol treatment, for instance. He noted some states allow convicted drunk drivers to obtain "work licenses," letting them drive to and from their jobs, if they have ignition interlocks installed.

Clegg said the judiciary committee discussed creating such a program here, but there was not enough support to make it part of this year's legislative changes.

State Rep. John Tholl, R-Whitefield, was one of the original sponsors of the interlock legislation. He said the program has been a long time coming.

"But I think if we can get it out on the street and get it going, then I think it'll save lives -- and hopefully change behaviors," he said.