According to a study done by GMAC insurance New York takes the cake. GMAC created a national driving test pulling questions from states all over the country. Click the link and take the test... see how you rank.
Here are the top 5 worst states, their ranking, and in parentheses their ranking for last year.
51: New York (51)
50: New Jersey (50)
49: Washington, D.C. (44)
48: California (48)
47: Rhode Island (46)
And...
The top 5 best states
5: Iowa (9)
4: Minnesota (11)
3: South Dakota (5)
2: Oregon (10)
1: Kansas (4)
Utah ranked 23rd (a sharp increase from last year at 7th), Arizona 17 (30), Maryland 20 (41), Massachusetts 38 (45), and Tennessee 19 (38).
Now while I think that there is some merit to this study, I don't think it is fair to label a state as the one with the worst drivers based on a written test with questions compiled from all over the country. I think that more research needs to be done including data collected in regards to actual numbers of say traffic citations, accidents, and so forth. But it was kind of fun after all.