Drugged driving: 20 states with highest rates

stoned, high, driver, under the influence, drugged, drugs, driving, stock, 4x3 — istockphoto

Think alcohol is the only substance that impairs motorists? Think again. Driving under the influence of drugs such as marijuana, cocaine and opiates is another big - and often overlooked - problem. Among drivers killed in accidents, 18 percent tested positive for at least one drug, according to a 2009 study by the National Highway Traffic Safety Administration. In which states is driving while high most common? Keep clicking to see the top 20, using 2006-2009 data from the Substance Abuse and Mental Health Services Administration...

20. Wisconsin

driving, wisconsin, traffic — Flickr/ladytaz

Wisconsin kicks off the list of states with the highest rates of "drugged drivers" - 4.8 percent of Wisconsin drivers acknowledged driving under the influence of an illicit drug at least once in the previous year.

20. New Mexico

albuquerque, new mexico, state, downtown — Flickr/Ken Lund

Percentage of motorists who acknowledged driving while drugged: 4.8

18. Washington

washington, roads, driving — Flickr/diamond_rain

Percentage of motorists who acknowledged driving while drugged: 4.9

18. Nevada

downtown, vegas, las vegas, nevada — Flickr/purpleairplane

Percentage of motorists who acknowledged driving while drugged: 4.9

18. Minnesota

driving, minnesota, roads, city, urban — Flickr/kevinmjack

Percentage of motorists who acknowledged driving while drugged: 4.9

15. Maine

Percentage of motorists who acknowledged driving while drugged: 5.0

15. District of Columbia

washington d.c., washington dc, capitol building, spring, generic, 4x3 — istockphoto

Percentage of motorists who acknowledged driving while drugged: 5.0

15. Connecticut

connecticut, driving, roads, suburbs — Flickr/Doug Kerr

Percentage of motorists who acknowledged driving while drugged: 5.0

12. Michigan

driving, michigan, road, intersection — Flickr/mindfrieze

Percentage of motorists who acknowledged driving while drugged: 5.1

11. Wyoming

Percentage of motorists who acknowledged driving while drugged: 5.2

10. Oklahoma

Percentage of motorists who acknowledged driving while drugged: 5.4

10. Delaware

Percentage of motorists who acknowledged driving while drugged: 5.4

10. Arkansas

Percentage of motorists who acknowledged driving while drugged: 5.4

7. Colorado

colorado, estes park, driving, rockies, rocky mountains — Flickr/Rasekh Fatmi

Percentage of motorists who acknowledged driving while drugged: 5.5

6. Oregon

driving, road, oregon, bridge — Flickr/lbjorn

Percentage of motorists who acknowledged driving while drugged: 5.7

5. Montana

montana, state sign — Flickr/J. Stephen Conn

Percentage of motorists who acknowledged driving while drugged: 6.0

4. New Hampshire

new hampshire, downtown — Flickr/Doug Kerr

Percentage of motorists who acknowledged driving while drugged: 6.1

3. Massachueetts

downtown, boston, massachusetts — Flickr/morethanreal

Percentage of motorists who acknowledged driving while drugged: 6.4

2. Vermont

vermont, generic, state, 4x3 — iStockphoto

Percentage of motorists who acknowledged driving while drugged: 6.6

1. Rhode Island

rhode island, state sign, generic, 4x3 — iStockPhoto

The smallest state has the biggest problem with drugged driving. In Rhode Island, 7.8 percent of motorists acknowledged driving under the influence of an illicit drug.