Question re admissibility of audiotape evidence by the defence

[SoPerplexed]

Could anyone enlighten me on the rules of admissibility of audiotape evidence by the defence in a criminal trial? I know that the rules for the prosecution to submit audio evidence are very strict, but are they exactly the same for the defence? Scenario below….

If Person A has made an allegation of assault by Person B, with person C as the lone bystander, can Person B be allowed to submit an audio recording that was supposedly made at the time of the incident as evidence in their defence? The recording was made covertly, probably on a mobile phone, if indeed it is genuine. I presume B would be required to prove the genuineness of the recording. Would it be enough for B’s assertion of the genuineness of the recording to be supported by C (the bystander, and a friend of B)? By the way, to add another element to this, B has been highly trained and is employed as a sound recording engineer and would thus obviously be highly skilled in editing or even possibly fabricating the recording entirely.

If B and C are the only ones attesting to the genuineness of the recording, would B’s defence have a hope in hell of getting it admitted as evidence?

[fifi333]

Is this an exam question?