Commerce Clearing House (CCH) Inc.’s 1999 Unscheduled Absence Survey estimates that excessive absenteeism costs corporate America
somewhere in the neighborhood of $600 per employee annually—a hefty toll, considering that not all absenteeism stems from legitimate illnesses. The first place to look when addressing excessive unauthorized absenteeism is your company policy. Many companies place caps on annual sick leave allowances; others refuse to write a policy for fear that the written document will limit their discretion in dealing with employees on a case-by-case basis. Your decision to implement a policy should depend on the frequency of worker absenteeism relative to industry and geographic standards.

In addition, setting policy can be challenging because employers need to determine the parameters of the program:
Will they measure actual days or ‘‘incidents’’ (i.e., an uninterrupted
series of days off from the same sickness or injury)?
Do they believe that a no-fault or an excuse-based system
will be more effective?
Will a rolling year or a calendar year serve as the optimal
performance measurement time period?

Beyond the nuts and bolts of your written policy, your past practice must also be closely examined. If you’re inconsistent in the application of your organization’s rules, a judge or arbitrator may determine that your fickle actions could justify a claim of discrimination or retaliation from a terminated worker.

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How much time off is considered excessive? There’s no easy answer, but juries typically consider one sick day per month, or twelve days a year, as a threshold. More than that and it’s likely that the discharge will be sustained; less than that and a plaintiff attorney may convince a jury that your decision to terminate was premature and possibly just a pretext.

Taken From : The Hiring and Firing Quention and Answer Book