Banner-Evaluation of Minnesota's High-BAC Law

3. Evaluation of Minnesota's High-BAC Law

Rates of Recidivism

Recidivism Rates by High BACs vs. BACs .17-.19

The recidivism rates for first-time high-BAC offenders arrested in 1998 were consistently about 2 percentage points lower than for the “comparison” group of offenders with BACs .17-.19 (Table 11).  Differences in the rates of recidivism after one year were 8.0 percent for BACs .17-.19 vs. 6.3 percent for high-BACs (X2 = 9.3,   df = 1, p = .001) and after two years were 14.2 percent for BACs .17-.19 vs. 12.6 percent for high-BACs (X2 = 4.5, df = 1, p = .03). 

The rates of recidivism among repeat offenders arrested in 1998 with BACs > .20 and those with BACs .17-.19 were generally comparable (Table 11).  Neither the recidivism rates after one year (6.8 percent for both groups) nor the rates after two years (14.4 percent for BACs .17-.19 vs. 14.4 percent for BACs > .20) were statistically significant.

Table 11

Rate of Recidivism for DWI Offenders Arrested in 1998, Minnesota
BACs .17-.19 vs. BACs > .20
Cumulative Percent of Offenders with Subsequent Offense

First-Time Offenders

Repeat Offenders

 

BAC .17-.19

BAC

 > .20

BAC

 .17-.19

BAC

> .20

Total Cases (N)

(4,058)

(4,056)

(1,389)

(1,814)

Months Elapsed since Arrest

%

%

%

%

3

  2.4

  1.8

  1.7

  2.6

6

  4.3

  3.4

  3.3

  4.1

9

  6.2

  4.7

  5.0

  5.6

12

  8.0

  6.3

  6.8

  6.8

15

  9.7

  7.8

  8.9

  8.5

18

11.4

  9.6

10.5

10.0

21

12.8

11.1

12.1

11.9

24

14.2

12.6

14.4

14.1

By the end of the first year following arrest, recidivism among high-BAC first-time offenders arrested in 1999 (6.7 percent) was lower than recidivism among first-time offenders with BACs .17-.19 (7.8 percent) (Table not shown).  This difference was marginally significant (X2 = 3.89, df = 1, p = .05).  For repeat offenders arrested in 1999, high-BAC offenders had a slightly lower recidivism rate than offenders with BACs .17-.19 after one year (7.2 percent vs. 7.7 percent).  This difference was not statistically significant.