Asking for a week off after two weeks?Watch
Mention that you're hoping to go on holiday for a week sometime in the next couple of months. Then when you get the job you can say a really good last minute deal came up and you had to book it - but you feel quite bad that you're asking for a week off so soon after you started. I don't think they can refuse you leave...
Or just be honest with them... tell them you've got the work experience at a law firm... It doesn't sound like you're going to be in the job you';re going for forever and they will probably know that too anyway