A4. The phonetic analysis

When I was made aware of this case in 2011 (after the final appeal was rejected), I undertook a detailed analysis of the audio and of the police transcript.

Before reading my remarks, you might like to listen to the 1-minute excerpt again (remembering it is an excerpt from 38 minutes of similar material).

This audio is quite typical of indistinct covert recordings used in many trials.

A question you might have wondered about: why don’t they just enhance audio like this to make it more intelligible?

Believe it or not, this is the ‘enhanced’ version. There’s a lot more that can and should be said about that, but it is not the most important issue in this case study so we won’t pursue it here. You can learn more about ‘enhancing’ and its problems elsewhere in this site.

So what can we say about the content of this recording?

While some parts are not capable of reliable transcription, other parts can, with the aid of background knowledge of the context, be interpreted with moderate confidence.

The problem is that assumptions or expectations about the context can be just as effective as reliable knowledge about the context in giving the listener a confident perception of what was said – hopefully you have seen some examples of how that works under The Cause.

That means that different listeners, making different assumptions about the context, can hear the same audio quite differently, and all with equal confidence. Intrigued with that idea? You might like to look into Learn More when you have finished with the Case Study.

For now, the upshot is: the only way to be sure which interpretation is correct, if any, is via phonetic analysis.


My analysis showed the detective’s transcript was unreliable and misleading throughout. In particular I was able to demonstrate that the words ‘at the start we made a pact’, which played such a crucial part in the trial, were never spoken.

In fact, nothing remotely like these words was spoken. So much so, it actually takes some effort to determine exactly which section the detective heard as this phrase – as you may have experienced for yourself.

Once the relevant section is found, however, phonetic and acoustic analysis demonstrates clearly that this phrase could not possibly be what was said.

Here’s a small part of what I did – a spectrogram of the section alleged by the detective to be ‘at the start we made a pact’.

pact spectrogramIt is not appropriate to go into technical details here, but as a brief indication, you can see which syllables are stressed from the darkness of the marks. To create a stress pattern like the one we see here by saying the alleged phrase, you would have to pronounce ‘at the start we {pause} made a pact’ – unusual to say the least. (There are other issues; this is just the easiest for non-specialists to observe).

But this transcription is so egregious, it is quite evident even to the untrained ear that it doesn’t fit the audio – if the phrase is presented in isolation, rather than embedded in a long audio file. Here it is. Do you think it sounds like ‘At the start we made a pact’?

So what DID he say?

It is evident that the phrase is not ‘at the start we made a pact’. Unfortunately, however, due to the very poor quality of the audio, it is not so clear what actually is said.

It is a phrase with an overall rhythm and sound structure something like ‘it’s fucking payback’.

Play it again and see if you agree

It is important to emphasise that the phrase is something like ‘it’s fucking payback’. Although people who listen to the audio with that suggestion are inclined to hear it that way, those who don’t get that suggestion hear all kinds of other things. Here’s just a few examples of what people have heard before a suggestion was made (remembering that most hear nothing at all):

  • bit stuck – phone y’ back
  • played it back
  • it’s a play back yeah yeah
  • get it stuck?
  • moneybag {or maybe playback, I’m not at all sure}???
  • it’s fucked, you know?? made it back
  • its back  / pay her back
  • Its back. I begged
  • it’s safe / play back
  • play it back
  • ? … pay you back …?
  • it’s like lying back
  • it’s back by
  • Yeah, yeah it’s fine.
  • Just that its laid/way  back
  • It’s fucked you made it back
  • it’s nothing …layin’ back
  • it’s stuck/dark..pay you back
  • its that that plain bag?
  • …pay ya back………..
  • It’s fucked bloody bad
  • it’s that bloody bank
  • it’s a biege bag
  • it stuck made it back
  • hitch back, fight back
  • its stuck playback

Phonetic analysis cannot positively confirm what was said

This section (like much of the rest of the audio) is not capable of reliable transcription. It has the status of a smudged fingerprint or inconclusive DNA evidence. The kind usually excluded from evidence, not admitted with a detective’s opinion to assist the jury.

A response to be wary of

I have heard some people say ‘Well if he said It’s fucking payback that makes him sound pretty guilty anyway’. Try hard not to think like that! Partly because the trial was about a pact not about payback, but more importantly because it is not clear at all that that is what he really said. On the other hand, the fact that people do think like that gives additional reasons (if we need them) for being very careful that only reliable transcripts are given to juries.

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