Question: Before firing or disciplining an employee for tardiness, ask yourself these two questions: Could he be covered under the Americans with Disabilities Act (ADA)? And, if so, how essential is his punctuality to the job?

While the ADA requires companies to make job accommodations for disabled workers, you don’t have to employ anyone who can’t perform the “essential functions” of the job. And on-time attendance is an “essential function,” right? Not necessarily, as the following case shows.

Case in Point: Tommy Holly, a paraplegic who uses a wheelchair, was an excellent employee at a Florida plastics manufacturing company for 17 years. He was sometimes late to clock in by a few seconds or minutes, typically because tables blocked his path to the time clock or he’d wait out rainstorms in the parking lot to prevent getting drenched.

The company informally accommodated his disability-related tardiness. But that all stopped when a new sheriff rode into town. The new HR manager introduced a no-excuses attendance policy that made absolute on-time arrival an “essential function” of every job. The new policy made no allowances for absences without a doctor’s note. Plus, the policy stated, “Employees with American Disability Act situations are not exempt from this policy.”

Holly was fired when his tardiness reached the policy’s cutoff number. Sometimes he was late one second, other times a minute or so. Under the policy, it made no difference. Nor was the HR manager swayed by Holly’s supervisors’ pleas to allow them to retain a hard-working team member.