Bad weather and rural roads are leading factors of DUI occurrences according to a new study by CarInsuranceComparison.com, a website that allows drivers to compare auto insurance rates.

The study used statistics from a variety of sources that measured these factors in each state:

• Percent of fatal crashes that involved alcohol
• DUI arrests
• Percent of drunk driving fatalities
• Cost of drunk driving facilities per taxpayer in the state
• DUI laws in the state that penalize 1-st time and repeat offenders ranked against averages in other states

These factors were weighted before ranking states, with fatality rates and DUI arrests receiving the most weight, followed by DUI arrests and DUI penalties.

The study found that the worst states for DUIs and alcohol-related car accidents are:

1. North Dakota
2. Montana
3. Idaho
4. Wisconsin
5. South Carolina
6. South Dakota
7. Pennsylvania
8. New Mexico
9. Rhode Island
10. Vermont

North Dakota had the worst fatality rank and DUI arrest rates in the country. Montana—ranked 2nd worst— has reported that over three-quarters of the fatalities within the last decade in the state are due to impaired driving or driving without a seatbelt. Utah ranked the lowest for alcohol-related driving accidents.

The statistics show that the states with the worst rates of alcohol-related crashes have a combination of bad weather and rural roads, both of which exacerbate DUIs. Inclement weather, like ice and snow, make roads more dangerous while rural roads tempt drivers to reach high-speeds.

The authors of the study note that there is no single takeaway from the statistics that point to specific policy changes that can create safer roads. However, there was a connection between strict DUI policies and reduced rates of alcohol-related crashes. Florida has some of the strictest DUI penalties in the country, and it subsequently has one of the lowest fatality ranks and DUI arrest ranks.

There is some positive connection between the distance drivers cover in a city and the amount of DUIs that occur. Another ranking of the strictness of DUI laws in states shows that the top five states with the most lenient DUI laws—South Dakota, Pennsylvania, North Dakota, Maryland, Montana—are all represented in the worst states for alcohol-related crashes.

But not all DUI laws are effective at curbing drunk driving. Studies have shown that lowering legal blood alcohol levels is not effective in reducing drunk driving. But other studies, like the ones mentioned above, have found a correlation between stricter laws and reduced drinking and driving. Some states, like Virginia and Arizona, have some of the strictest DUI laws but still have DUI statistics that are slightly above average. Mostly it depends on unique situations within the state: who is drinking, where are they drinking, and why are they driving while intoxicated.

Governments will need to continue to pursue comprehensive campaigns against drunk driving, both to enforce strict penalties for those who do drink and drive and to spread public awareness about the devastating effects drunk driving can have on victims of crashes and on the drivers themselves.