Since Jan. 1, 2012, ignition interlock devices have stopped more than 21,500 would-be drunken drivers from starting their cars in Connecticut, according to a report released by Mothers Against Drunk Driving last week.  

Experts expect that number to climb at a faster rate in the coming years given the state's recently passed "all-offender" law.

On July 1 of last year, Connecticut became one of the 25 states that require or highly encourage all who are convicted of drunken driving, even first-time offenders, to install ignition interlock devices in their vehicles.

After undergoing a 45-day driver's license suspension, first-time offenders in Connecticut are required to install the devices, which prevent a car from starting if any alcohol is detected on a driver's breath, in any car they own or drive, at their expense, for six months.

According to MADD's report, all 50 states have some type of ignition interlock device law. Some only require the devices for repeat offenders. Others impose them on first-time offenders only if the person's blood alcohol content is 0.15 or higher, or if a judge orders it.

"The whole goal of the devices is try to change behavior," said Janice Heggie Margolis, executive director of MADD's Connecticut office. "So this study is extremely important to the country and to Connecticut because it shows very significantly that the device works."

Across the country, MADD's numbers — drawn from data through Dec. 1, 2015, provided by ignition interlock companies — show the devices have prevented almost 1.8 million people with a blood alcohol content of 0.08 or more from driving.

For some states, the numbers have been complemented by sharp declines in drunken-driving fatalities.

In Arizona, where an all-offender ignition interlock device law was passed in 2007, data from the National Highway Transportation Safety Administration's 2014 Fatal Analysis Reporting System shows a 50 percent decrease in such fatalities since 2006.

Nationally, the reduction since 2006 is 26 percent.

Ten other states have seen a reduction of 10 percent or more since their  laws began requiring or encouraging ignition interlock devices for all convicted drunken drivers.

Only two of the 25 states — Nebraska and Utah — have seen an increase of 10 percent or more in drunken-driving fatalities since enacting their laws.

In Connecticut, the number of drunken-driving fatalities was 94, 100, 114 and 97 in 2011, 2012, 2013 and 2014, respectively. Numbers for 2015 are not available.

That's about a 3 percent increase in fatalities since 2011, comparable to the 1 percent increase that's happened nationally since then.

Frank Harris, director of state government affairs with MADD national, said the increase is not a cause for concern, since the new law has only been in effect since last July.

"We're going to need at least another year, especially with the new law ... for there to be a noticeable difference in drunk-driving deaths," Harris said, explaining that first-time offenders make up the majority of DUI offenders.

Under the state's ignition interlock device law that was effective from Jan. 1, 2012, to June 30, 2015, only repeat offenders were required to use the devices.

At any given time during that period, Margolis said, about 1,000 people were using them. Connecticut, however, has about 10,000 DUI arrests per year.

"Of course our goal going forward is to get all 10,000 offenders using the devices," she said. "But I can't tell you specifically that every person will. They may be ordered to (install the devices) by the courts, but it's the responsibility of the offender to do so."

According to MADD, Connecticut drivers must pay the state Department of Motor Vehicles $175 to reinstate their licenses and $100 more to get an interlock installation application.

From there, Margolis said, it's about $75 to lease the device from one of the state's six authorized vendors and an additional $50 per month to have it calibrated.

MADD is prohibited from accepting funds from ignition interlock device companies, Margolis noted.

For those who think the costs associated with installing and maintaining the devices are too high, she had some strong words.

"I believe that saving lives is critical to the program and our campaign to eliminate drunk driving," Margolis said. "If someone chooses to drink and drive and has (blood alcohol content) greater than 0.08 ... they've got to pay the consequences. We're not talking about someone who went to dinner and had a glass of wine."

Besides, she said, it's better than a license suspension.

"Our hope is that it's not viewed as punitive measure, but as an opportunity to continue with life," Margolis said.

In the report, MADD suggested Connecticut officials should consider requiring the devices as soon as after an arrest, such as eight states do, including some that have seen the sharp declines in drunken-driving fatalities.

But because of all the variables involved — number of drivers, number of miles drivers travel, length of time a state's interlock device law has been established — it's hard to compare Connecticut's numbers directly to those of other states, Margolis said.

"What I can say is we had a legislature that saw the need to pass an all-offender ignition interlock device law in 2014," she said.

While 97 people were killed in drunken-driving crashes in Connecticut that year, nationally the number was closer to 10,000.

"We know from the study that hundreds, thousands of people's lives have been saved because the devices are in the cars," Margolis said. "Can we say we are saving lives? Absolutely. Can I tell you how many? No."

l.boyle@theday.com

Twitter: @LindsayABoyle