Drunken driving overturned

Driver who crossed fog line was stopped without enough reason, appellate judge rules

How are people like this allowed to be judges?
Why is it that judges are always trying to make the job of cops harder, basically taking away common sense and observation.
I just don't understand.
You have someone who is driving over the line more than once...MAYBE they are drunk. The cop should pull them over and find out. If they are not drunk, you can let them go. Good police work got a drunk off the streets, and an idiot judge put him right back on.
Is common sense completely dead?
link of judge