Many thanks for your patience. First of all you have over 2 years’ service with the employer which means you are protected against unfair dismissal. This means that to dismiss you the employer has to show there was a fair reason for dismissal and that a fair procedure was followed. Conduct is a potentially fair reason for dismissal so it will come down to whether it is relevant here and also whether the procedure they followed was fair.
As there is no automatic legal obligation on employees to disclose police investigations they are subject to, whether such a failure was a misconduct offence will very much depend on the contract and internal policies. So you need to check these to see if there was a specific obligation on you to make such a disclosure to the employer because that would be the only time they can try and argue that you had been guilty of misconduct. The misconduct would be that you had failed to follow a specific contractual obligation you had.
Even if there was such an obligation on you and you failed to follow it, it does not mean it would automatically amount to gross misconduct. It has to be serious enough to qualify so it would depend on whether it impacted your ability to do your work in any way, such as if you were a teacher and were investigated over child abuse offences, or if you were a banker and were being investigated for fraud…these kind of situations. But I would say that the fact you were only under investigation, never charged or convicted, means you are technically innocent so regardless of what the allegations were, you are officially an innocent man so the offence of not informing them should not be viewed that seriously.
This is your basic legal position. I have more detailed advice for you in terms of the rights you have should you still get dismissed, which I wish to discuss so please take a second to leave a positive rating for the service so far (by selecting 3, 4 or 5 stars) and I can continue with that and answer any further questions you may have. Don’t worry, there is no extra cost and leaving a rating will not close the question and we can continue this discussion. Thank you