People of a certain age in the islands have no doubt experienced being asked for some identification or their birth date when shopping for liquor or tobacco, even if it’s pretty obvious that it’s been years since they passed the legal age of 21.

Senate Bill 1398, which has a hearing Thursday, would prohibit a business that sells age-restricted goods from asking customers for the date of birth “if it is clear that the individual has attained the age required to make a purchase.”

The bill, introduced by Sen. Les Ihara, cites the Hawaii Constitution’s article on privacy — a right that “is recognized and shall not be infringed without the showing of a compelling state interest. The legislature is charged with taking affirmative steps to implement this right.”

It’s one thing for retail clerks to ask “youthful” customers for their birth date, the legislation reasons — it’s illegal to sell to minors, of course — but quite another thing for them to “routinely” require elderly customers to disclose their birthdates “usually within earshot of others.”

Doing so, SB 1398 suggests, amounts to age discrimination.

How, then, to define when it is “clear” a customer is old enough to buy alcohol and tobacco?

The bill explains that a “clear and convincing standard” means the existence of a fact or facts “that make the determination highly probable.”