I wouldn't employ her, due to her lack of transparency over it.
If she had disclosed, and you were happy with the circumstances around it, then I wouldn't let it be a barrier to employment.
I say this as a teacher who went drinking with 10+ colleagues straight after school for end of term drinks and dinner. Only 1 person chose non alcoholic drinks. The rest of us all had a couple of alcoholic drinks, then drove ourselves home. The deputy head was convicted of drink driving on her way home. She'd had 2 white wine spritzers over 4 hours. With food.
The reality was some of us would have been over the limit too, due to our body shapes and being female, but we weren't caught like she was. Had we thought any one of us was over the limit, we'd have stopped ourselves driving. In a group of professionals that large, including the headteacher, none of us thought anyone was over the limit.
The UK limit is so dependent on the person drinking, and the level of alcohol in the drink. If the wine in the spritzer was 8% she'd likely have been under the limit. Who asks what % a wine is when ordering?
She didn't lose her job, and went on to get her first headship last year, 2 years after her conviction. So it isn't a barrier to teaching. Seemingly, the appointing panel listened to her story and acknowledged we all make mistakes.
The only safe way to be under the limit is driving with no alcohol at all.