| State | MLDA21 Law Effective Data | Zero Tolerance Law (<0.02 BAC, Age Under 21) |
|---|---|---|
| Alabama | 10/1/85 | 5/28/96 |
| Alaska | 11/1/84 | 8/10/96 |
| Arizona | 1/1/85 | 6/28/90 |
| Arkansas | 1935 | 8/12/93 |
| California | 1933 | 1/1/94 (Previously 0.05 Age < 18) |
| Colorado | 7/1/87 | 7/1/97 |
| Connecticut | Age 21 9/1/85 Age 19 to 20 10/1/83 Age 18 to 19 7/1/82 |
10/1/95 |
| Delaware | 1/1/84 | 7/1/95 |
| Florida | Age 21 7/1/85 Age 18 to 19 10/1/80 |
1/1/97 |
| Georgia | Age 21 9/30/86 Age 19 to 20 9/30/85 Age 18 to 19 9/1/80 |
7/21/97 (Previously 0.06 Age < 18) |
| Hawaii | 10/1/86 | 12/1/97 |
| Idaho | 4/10/87 | 7/1/94 |
| Illinois | 1/1/80 | 1/1/95 |
| Indiana | 1934 | 1/1/97 |
| Iowa | Age 21 9/1/86 Age 18 to 19 7/1/78 |
7/1/95 |
| Kansas | 7/1/85 | 1/1/97 |
| Kentucky | 1938 | 10/1/96 |
| Louisiana | 3/15/87 | 7/15/97 |
| Maine | Age 21 7/1/85 Age 18 to 20 10/24/77 | 9/29/95 |
| Maryland | 7/1/82 | 5/29/90 |
| Massachusetts | 6/1/85 | 6/27/94 |
| Michigan | 12/21/78 | 11/1/94 |
| Minnesota | Age 21 9/1/86 Age 18 to 19 9/1/76 |
6/1/93 |
| Mississippi | 10/1/86 | 1998 |
| Missouri | 1945 | 8/28/96 |
| Montana | Age 21 4/1/87 Age 18 to 19 1/1/79 |
10/1/95 |
| Nebraska | Age 21 1/1/85 Age 19 to 20 7/19/80 |
1/1/94 |
| Nevada | 1935 | 7/16/97 |
| New Hampshire | Age 21 6/1/85 Age 18 to 20 5/24/79 |
1/1/93 |
| New Jersey | Age 21 1/1/83 Age 18 to 19 ½/80 |
12/17/92 (Previously 0.04 Age < 21) |
| New Mexico | 1934 | 1/1/94 (Previously 0.05 Age < 18) |
| New York | Age 21 12/1/85 Age 18 to 19 12/4/82 |
11/1/96 |
| North Carolina | Age 21 9/1/86 Age 18 to 19 10/1/83 |
9/15/95 (Previously 0.00 Age < 18) |
| North Dakota | 1936 | 7/1/97 |
| Ohio | Age 21 7/31/87 Age 18 to 19 8/19/82 |
5/4/94 (Previously 0.02 Age < 18) |
| Oklahoma | 11/1/85 | 11/1/96 |
| Oregon | 1933 | 7/1/91 |
| Pennsylvania | 1935 | 8/2/96 |
| Rhode Island | Age 21 7/1/84 Age 19 to 20 7/1/81 Age 18 to 19 7/1/80 |
6/30/95 (Previously 0.04 Age < 18) |
| South Carolina | Age 21 9/14/86 Age 19 to 20 1/1/85 Age 18 to 19 1/1/84 |
7/1/93 |
| South Dakota | Age 21 4/1/88 Age 18 to 19 7/1/84 |
1998 |
| Tennessee | Age 21 8/1/84 Age 18 to 19 6/1/79 |
7/1/93 |
| Texas | Age 21 9/1/86 Age 18 to 19 9/1/81 | 9/1/97 |
| Utah | 1935 | 7/1/92 |
| Vermont | 7/1/86 | 9/1/97 (Previously 0.02 Age < 18) |
| Virginia | Age 21 7/1/85 Age 18 to 19 7/1/81 |
7/1/94 |
| Washington | 1934 | 7/1/94 |
| West Virginia | Age 21 7/1/86 Age 18 to 19 7/1/83 |
6/12/94 |
| Wisconsin | Age 21 9/1/86 Age 18 to 19 7/1/84 |
10/14/97 (Previously 0.00 Age < 19) |
| Wyoming | 7/1/88 | 1998 |
Sources: NHTSA; Insurance Institute for Highway Safety; O'Malley and Wagenaar (1991).