Over five years in this post, around 15-20 years service with NHS.
Hi there is no problem with the employer having an investigation meeting based on hearsay. If the employer takes disciplinary action or refers you to occupational health without reasonable belief that there is an issue for you with alcohol then that would give you grounds for complaint.
If this does, in fact, occur I would advise you to raise a grievance or to appeal against any disciplinary action.
If you would like any further information please do let me know.
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