Yes, random sobriety tests for drivers are a good idea, because drunk driving is a pervasive problem. If a drivers pays attention to other drivers on the road, they will appreciate what a big problem drunk driving is. At any given time, a driver can encounter what is akin to a moving missile. Combating the problem through random testing is fair to everyone and will save lives.
Random breath test for drivers is a good idea. Drunk driving is far too dangerous to be
tolerated. Many drivers continue the
habit of drunk driving because they feel that they will never get caught. If they saw more random checkpoints on the
road, they may be less likely to drive drunk at all.
Random checks assume without probable cause that people are guilty of drunk driving.
The argument that this may reduce drunk driving is a poor one. The same logic could be used to justify random searches of people's houses to find drugs. Or to set up video cameras with no probable cause in college dormitories to catch rapists.
Bill of Rights prohibits unreasonable searches. When the government physically intrudes on "persons, houses, papers, or effects" for the purpose of obtaining information. Probable cause is the standard by which an officer of the law has the grounds to obtain a warrant for conducting a personal or property search. P.S. I do not drink or take drugs.