There are instances where an employer may need to determine an applicant's age. The interviewer can ask a young interviewee if he has appropriate working papers. If the job requires that an applicant is of a legal minimum age for the position (i.e. bartender, etc.), the interviewer can ask as a pre-requisite to employment that proof of age be furnished. If the company has a regular retirement age, they are permitted to ask if the applicant is below that age.