I think this is what you are trying to say: "I believe that the police should be hard (alternative: harsh) on those who drive drunk (alternative: drink and drive), even though they are short-staffed." Adding the word 'while' makes the sentence sound a little more natural and makes it flow better, but isn't necessary for the sentence to be grammatically correct: "He drove the car while drunk." I hope this helps! :)

In the first sentence, this is what you are trying to say. I am not sure if you think the police should be harsh or assume that the police is harsh on those who drink and drive. I went with the first assumption: "I think/opine that the police should be hard on those who drive drunk(alt: drink and drive), even if they are short on staff." Second it should be drunk not drunken, I am not sure about the grammar, but drunk sounds right He drove the car drunk.