Poor performers get put on PIPs, right? Did that person's poor performance "ruin it for everyone" and put the rest of the working plebs (the entire company or department or whatever) on PIPs? No, of course not. The poor performer gets singled out, which is just fine.
So instead of punishing everyone for some lying asshole's poor judgment, I propose management puts that lazy jerk on their own SDIP (sick day improvement plan).
EDIT: As an alternative, sure, update the handbook's sick policy while that liar is working for you. Since there's now precedent for handbook updating, should be an easy thing to revert it back to the normal, "no sick day policy" after they leave (by whatever means).
> The poor performer gets singled out, which is just fine.
he's not a poor performer, he's just an asshole. And you can't fire someone for being an asshole
> So instead of punishing everyone for some lying asshole's poor judgment, I propose management puts that lazy jerk on their own SDIP (sick day improvement plan).
You're missing the point. You can't single the person out for violating a policy that you didn't have written down. The only reason that policy is now written down is because that person violated the policy. Singling out someone for being (genuinely) ill is likely to end up with you on the wrong end of an employment tribunal who will ask you "what is your sickness policy"