Should I sack Employee for criminal past ?

Should I fire employee for his criminal past?
I have discovered that an employee has a criminal record. While the employee is a very good worker, he did not reveal his convictions at interview. I am also concerned that a client became aware of this and I do not want this to affect the reputation of my company. Can and should we take any action against him?
You are not required to take action, but if you did, there are legal risks. Even if your employee was asked about his criminal record, “spent” convictions would not usually need to be disclosed.
Subject to a few exceptions, an offender is deemed to be rehabilitated and their convictions become spent after a specified period. Dismissal for failing to disclose spent convictions would almost certainly be unfair. But if your employee lied about his criminal record because his convictions were not spent, you can sack him for breach of trust and confidence.
Regardless of the interview, if you can produce evidence that the client relationship had in fact been compromised or the company’s reputation had been damaged as a result of the employee’s convictions, then there are potential grounds for dismissal, especially if this is a major client. In looking at whether any dismissal was fair, even if there are good grounds for action, a fair dismissal process would still be needed.