In the United Kingdom:
Is it legal to secretly audio record a meeting (in an office) or a phone call while being a participant?
Is it possible to use such recording as an evidence in court or employment tribunal?
To preface my answer, this aspect of UK law is unclear at best and I try to set out general principles where available.
a) If you are acting in a private sphere, then the recording of conversations are unregulated, however this is only for personal use - i.e. should you desire to make notes on what was said for your reference at a later date. Should you wish to share it with a third party, then you would need consent from all participants or be able to demonstrate that it would be in the public interest.
b) If you are acting as an employee or a company, then the situation changes. Firstly, you need to check your contract, whilst this does not constitute a crime, it may be against the terms of your employment. Secondly, a company can only make recordings without knowledge under statutory conditions, such as to establish facts, ensure regulatory compliance or demonstrate standards that are achieved or need to be achieved by training.
It is a general principle that conversations recorded without consent are inadmissible in court, particularly in terms of a criminal proceedings. In civil matters, it similarly follows the concept that a claimant should come to court with 'clean hands'. However, judges are usually more pragmatic in civil cases and if parties are aware of the existence of the recording, then it often be subject to usual rules of disclosure, though this may open the creator of the recording to subsequent litigation regarding the illegality of the recording under Data Protection Act or others.
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