But they don't and that's the point. The 'intrusion' in the OP is tantamount to a 30 second wait in line. If you have to piss in a cup each time you get in the car then I would be both amazed and sorry for you and your countrymen for the laws you have and the hoops you jump.
Honestly I don't see much distinction between blow in this tube and peeing in a cup. Random police stops bother me much more than either one though. My main concern here is the tradeoff between "making everyone safe" which these actually fail to do anyway since habitual drunks are going to get into a car anyway, and eroding the rest of our freedoms. These kinds of checkpoints are common place in a lot of 3rd world areas and are used for various forms of population controls. If the gov can setup checkpoints whenever they feel like it for DUI they can use that as a cover for a lot of other nefarious stuff.
Now again, you live in Australia. The cops here are very militarized and have watch too many actions movies. I think there is a legit threat to the population by giving these jokers too much power. We do have fairly strong constitutional prohibitions against this kind of nonsense but they are slowly being eroded by the courts.
I am also sorry to hear about your parents, I hope they are OK. Given same I would have thought you would support any laws that might stop people being hurt.
My brother got into a wreck when a drunk guy pulled out in front of him too.
And no, I already think drunk driving laws are too harsh. If I could snap my fingers and magically make all the drunks go away I would. I just see laws as a very blunt tool for dealing with stuff like this. Hardcore alcoholics are the chronic drunk drivers who cause most of the accidents. They already get ensnared in the system but drive anyway. The only way to stop some of these jokes is to throw them in jail. Making travellers illegal isn't going to make any difference for them but it is going to limit the freedom of others.
I just think it's possible for the pendulum to swing too far in the harsh enforcement direction and therefore cause more problems than it solves. It sounds like Australia maybe hasn't reached that point.... something like travellers would utterly shock people around here.
The drug war is an even better example of eroding freedoms for some while at the same time making everyone less safe through militarization of the police, erosion of rights and an incentivization of black market and often violent activity.
