Which is a vital step when checking someone's age with an ID?

The vital step when checking someone's age with an ID is to confirm that they are at least 21 years old. In Illinois, the legal drinking age is 21, and it is crucial for bartenders, servers, and other staff in establishments that serve alcohol to verify that individuals meet this legal requirement.

This process helps ensure compliance with state laws and prevents underage drinking. Simply asking someone their age verbally does not provide reliable verification because individuals may not always provide accurate information. While confirming the age by inspecting the ID, it is essential to look specifically at the birth date to calculate whether the person is of legal drinking age. Thus, confirming they are at least 21 encompasses the fundamental legal responsibility when serving alcohol.