There’s a clear difference between someone who’s drunk screwing up the alphabet, slurring, can’t keep their eyes open, getting distracted, arguing with the cop, unbalanced, and someone just not really remembering the alphabet. If you’re taking a field sobriety test, they’re not really grading your knowledge of the alphabet, they’re looking for signs of intoxication. If after all the tests (walk and turn, balance on one leg, looking at the horizon) the cop is still suspicious, you might do a breathalyzer, or be arrested and brought in for a blood test.
There’s a clear difference between someone who’s drunk screwing up the alphabet, slurring, can’t keep their eyes open, getting distracted, arguing with the cop, unbalanced, and someone just not really remembering the alphabet. If you’re taking a field sobriety test, they’re not really grading your knowledge of the alphabet, they’re looking for signs of intoxication. If after all the tests (walk and turn, balance on one leg, looking at the horizon) the cop is still suspicious, you might do a breathalyzer, or be arrested and brought in for a blood test.