(I posted this in Skinner's "Was alcohol involved?" thread, but there were 200+ posts by the time I had enough time to do the research and post the info, which is interesting enough to actually be read. :))
I went searching for statistical predictions of DUI behavior based on number of convictions, something along the lines of "for every conviction, a child molester has assaulted XX number of children." I didn't find exactly that, but instead found government studies that paint a more comprehensive picture of the DUI repeat offender.
These statistics come from
"Repeat Offenders and Persistent Drinking Drivers in the U.S.," a 1993 study by James Hedlund and James Fell of the National Highway Traffic Safety Administration. These stats seem to beg the question,
"When are repeat DUI offenders not under the influence?" Some excerpts:
-snip-
PERSISTENT DRINKING DRIVERS IN THE LITERATUREDWI Personality and Attitude (compared to all drivers)Frequently aggressive and hostile; more frequently sensation-seekers; more likely to have histories of other criminal behavior; minimize the risks of impaired driving -- they do not consider impaired driving a serious issue and rarely feel that they are too impaired to drive.
DWI Drinking BehaviorAt least 2-3 times a week; 13-38% daily drinkers; frequently have 5 or more drinks at a time (35-60%); mean BAC (blood alcohol level) 0.18 - 0.28; drink beer (64-79%); drink in licensed establishments (40-60%) more frequently than in private homes (18-34%); frequently had a previous problem due to drinking -- marital or family difficulties (30-49%), previous DWI (20-28%); frequently problem drinkers (54-74%)This summary doesn't specifically address the persistent drinking driver. However, it's clear from the description of the drinking behavior that these persons are persistent drinkers, and it's fairly safe to infer that many are repeat DWI offenders most are persistent drinking drivers as well.(sic)
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The study also summarizes the results of a random phone survey in which 56 respondents were self-admitted persistent drinking drivers. While the authors caution that this is a very small sample, what is interesting is the different profile that emerges of this "uncaught" drinking driver versus that compiled using convicted DUI offenders. The individual stats are very interesting but I'll cut to the summary:
-snip-
These respondents certainly fit the definition of persistent drinking drivers:
they drink frequently (almost every day) and drink and drive frequently (more than twice a week). However, they differ in important respects from the crash-involved drinking drivers in FARS and in the literature. They are somewhat older, they drink at home rather than in bars or taverns, and they don't drink as much at one sitting. They believe that drinking and driving is an important highway safety problem and they seem to accept DWI laws at approximately current BAC levels. They also have a far higher expectation of detection, arrest, and sanction if they drink and drive than occurs in practice. Again, these results must be interpreted with caution. They are self-reported data from a small sample in a telephone survey.
http://www.druglibrary.org/schaffer/MISC/driving/s21p2....-----------------------------
I also found a Canadian government study that cites some of the same literature as the NTHSA study but goes into greater depth about the personality characteristics of the DUI repeat offender. One excerpt from this substantial section:
-snip-
A number of studies have attempted to identify the social, psychological, behavioural and attitudinal characteristics that distinguish DWI offenders from other drivers (Donovan et al., 1983; Jonah and Wilson, 1986; MacDonald, 1989; Selzer et al., 1963; Cosper and Mozersky, 1968; Yoder and Moore, 1973; Meck and Baither, 1980; Fine and Scoles, 1974; MacDonald and Pederson, 1990; Perrine, 1975; Steer and Fine, 1978).
Some of the factors examined include hostility, aggression, sensation seeking, depression, attitudinal intolerance of drinking-driving, attitudinal intolerance of deviant behaviour, attitude toward driving, and health-compromising behaviours. In general, a common theme that emerges from these studies is that DWI offenders tend to exhibit a greater degree of deviance on most factors than do other groups of drivers.
www.hc-sc.gc.ca/ahc-asc/pubs/drugs-drogues/
dwi_systhesis-cfa_synthese/characteristics-caracteristiques_e.html
(combine the two lines for the full address)
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This, then, is the relevance of two DUIs, no matter what the age of the offender, the lag time between convictions or the apparent cessation of DUI behavior. These studies appear to confirm what common sense tells us: that someone with more than one DUI (
only 30% of convicted offenders) is more likely to drink frequently and have more alcohol-related problems.