I think you will find the answer in our justice system. Many years ago magistrates started getting soft on drink drivers. (Well, soft on every criminal) In Queensland it was mandatory for repeat drink drivers (basically 3 high readings in 5 years) to get jail. That changed and it is now rare for someone to get jail. I have seen many people who are habitual high end drink drivers go to court, plead guilty, their solicitor tells the court how sorry they are, valued member of the community, etc etc, and the magistrate sentences them to jail, but immediately suspends the time. No deterrent at all.
Having been a cop for over 30 years, (now retired) investigated countless fatal collisions, charged hundreds of drink drivers, there is a huge difference between people who are accidently just over the limit and others who are way over and deliberately drove knowing they were way over.
There are different penalties for the different readings and so it should be. We all are not perfect and we all make mistakes. Hopefully our mistakes do not cause harm to anyone else.
And believe me, there are more dangers out there then drink drivers. I know!
And be careful of the statistics about the number of crashes where alcohol is a contributing factor. If you saw how the stats are gathered, you would know what I mean.
How about we make people more accountable for their actions? Bring back penalties that should be a deterrent to all of us. That is for all offences.
Sorry to carry on, but I do speak from experience. And I could say a lot more.
Kevin