This action by police is nothing less than the same kind of thinking that is the substance of a " police state." It is not the right of law enforcement to randomly check to see if one has had, in their opinion, " too much to drink." I know for a fact that some people can be "drunk" and drive better than most people who have had nothing to drink.
If one wants to use the argument that this action saves lives then why don't we, as a nation, have laws governing the use of private swimming pools to the extent that we should, mandatorily, have government certified life guards posted at all private pools. After all, many more people die from drowning than being killed by a drunk driver.