Can I back date a Medical Certificate?

My resident doctors have been asking me what to do if they have patients who request to backdate their medical certificates.

"Sir, I have several patients come in to request for medical certificate because they want to be excused for their absence. Given that it is true, can we help them be excused so they get their salary by backdating the medical certificate? Is this ethical or not?"

For the sake of ethical discussion and not considering the legal implications, do you think it is ethical or not?

Veracity is the ethical principle of truth telling. Deontologists will tell us that doctors are duty bound to be truthful in their actions. Utilitarians will argue to do the action that will benefit the most good to all. But what about the character and values of the doctor that they must exhibit?

Truthfulness is a virtue that humans, especially virtuous doctors possess. What then should a virtuous doctor do when faced with a similar situation where a patient asks him to backdate a medical certificate? A virtuous doctor is expected to be truthful and would not lie about the date written in the medical certificate. He might, however, truthfully put a remark that the patient may have been sick for several days covering the dates that he was absent.