Other Grounds for Fair Dismissal
Capability and conduct are not the only grounds for dismissal. Whether you are justified in dismissing on other grounds depends on the facts of each case.
You cannot be expected to continue employing an employee if such employment is contrary to the law. Examples may include an employee losing their right to work in the UK, a sales representative who has been banned from driving or a doctor or lawyer who has been struck-off (a statutory bar). However, you should still act fairly and reasonably in taking the decision to dismiss and take into account the length of the disqualification, the employee's service record, your business needs and possible alternatives to dismissal. You do not need to create an alternative job if there an alternative is not reasonably available.
In all cases, the test for assessing whether a dismissal was fair is whether you, as the employer, acted reasonably in deciding to dismiss the employee. Again, taking advice in such circumstances is important.
Striking Workers
An employee can be dismissed for taking part in unofficial industrial action e.g. if the union has not held a properly organised ballot.
However, in the case of "protected industrial action" under the Employment Relations Act 1999, if an employee is dismissed as a result of taking part in such action the dismissal will be automatically unfair.