As a month of enhanced DWI patrols wraps up on New Year's Eve, officials say they believe that such patrols have made state roads safer since they began statewide in 2002.

"I would argue that having enforcement out there certainly does make a difference as shown in the number of drunk drivers arrested," State Patrol Capt. Matt Langer said Wednesday of the patrols, which have put dozens of extra officers on metro area roads.

Since DWI saturation patrols began seven years ago, impaired-driving fatalities have gone down, said Nathan Bowie of the Department of Public Safety. The highest death toll in that period was 255 deaths in 2003; the lowest was 153 fatalities in 2008, an all-time low.

Alcohol-related crashes declined from 5,652 in 2002 to 4,245 last year, Bowie said.

Over the past five years, a total of 1,688 impaired drivers were arrested statewide on New Year's Eves and New Year's Days, Langer said. In that period, each New Year's averaged 337 DWI arrests, second only to St. Patrick's Day, which had an average of 345 arrests per year over the five-year period.

During the same period, New Year's Eve and Day have seen 198 alcohol-related crashes, tied with July 4th for the highest holiday tallies, state records show.

The enhanced patrols, implemented by about 400 local, county and state police agencies, are publicized in ads and on highway signs, a practice the patrol believes adds a deterrent effect, Langer said.

"Every time we take a drunk driver off the road, we potentially prevent one those tragedies," he said.

Research has shown that the most effective way of stopping drunken driving is using sobriety checkpoints, where all vehicles are stopped and drivers given sobriety tests, said Jean Ryan, of the state Office of Traffic Safety. However, she noted, the practice was dropped in the 1990s after a Minnesota court ruled checkpoints unconstitutional.

"The fear of apprehension is the largest deterrent to reduce impaired driving," Ryan said.

In addition to saturation patrols, stronger DWI laws and greater use of seat belts have been important factors in the decline of impaired-driving fatalities, Bowie said.

He noted that a phone survey about this year's August-Labor Day DWI enforcement campaign indicated that the number of people who'd heard about increased enforcement rose from 37 percent before the blitz to 81 percent afterward.

Bowie said total traffic fatalities also have dropped from 657 in 2002 to 455 last year, the lowest since 1945. As of Wednesday, this year's traffic fatalities totaled 396, but an unknown number haven't been reported yet, he said.

"In the end, enforcement can only do so much," Bowie said. "It comes down to motorists taking driving seriously and getting in the habit of always having a plan to avoid getting behind the wheel impaired."

Jim Adams • 612-673-7658