There was one gun that fired all bullets. This is common ground to all parties.
There has been talk of two silencers, but that is also a red herring, no silencer was involved in the shootings that evening.
Are we sure that only one gun was used, though? When I looked into this case a couple of years ago, I got quite deeply into the material, including the ballistics evidence, and it seemed to me at least plausible that if Sheila did this, then two guns were used.
I don't have all the details to hand now, but the scenario in outline would be simple:
(i). She empties the first rifle.
(ii). She then grabs another rifle lying around and empties that one.
(iii). Having noticed ammunition near that rifle, she goes back and puts one more cartridge in the magazine, so she can kill herself. Obviously, being inexperienced, she doesn't take account of the fact that the rifle is not ideal for the task and may not kill her. She's deranged and doesn't care anyway.
(iv). She shoots herself in the neck and dies some hours later of cardiac arrest.
(v). She overlooks that there's also a cartridge left in the chamber. A second shot implies that she has either shot herself, but was still conscious and shoots again in frustration, or there was an accident by a third party when handling the rifle.
A possible variation on the above is that instead of putting a single cartridge in the empty magazine, she uses a second pre-loaded magazine, but the problem with this is how would she 'know' that there is only one cartridge left in the chamber? I remember looking into this and can't remember what I discovered about the rifle.
Does the bolt lock back in the open position on the 525 Model? I think it does. If it does, that surely is a problem for Bamber's defence. It means that while it is still plausible that Sheila could have been the killer, it's at the very lower end of plausibility because it would require Sheila either to have gone on a frenzy but left one bullet in the rifle then added another cartridge, or emptied the rifle and then added two cartridges. Neither of those scenarios make sense, I'm afraid. She wouldn't have added another bullet for good luck. I allow that the rifle was sub-optimal for its purpose, but Sheila isn't considering that, she just wants to point the rifle at her brain and fire. She only needs one bullet for that. Whether she actually kills herself, or has killed anybody else, is incidental. Or are we saying she planned the whole thing through? If so, what was she planning, given that she concludes this scenario by killing herself?
Unfortunately, it does point to Bamber. The scenario would be:
(i). Bamber puts two cartridges in the chamber, to give the impression that Sheila has gone on a frenzy and then shot herself.
(ii). Bamber fires once. It's probable that the first shot is the one that led to Sheila's death.
(iii). Bamber then accidentally fires a second time into the fleshy part of her neck after trying to get Sheila's finger mark on the metal plate.
(iv). Bamber doesn't trouble himself to add another cartridge or two, or decides not to, or just forgets.
Sorry.
I do still think the verdicts should have been Not Guilty, due to the following:
1. Essex Police compromised the crime scene, which means my tentative conclusion above is unreliable as it is based on compromised evidence and impressions. Do we even know for sure it was
that rifle? Etc., etc. The points are numerous. Given that the case against Jeremy is entirely circumstantial, this weakens the prosecution fatally.
2. There is no reliable evidence that the moderator was ever used in the killings, and it is not in itself reliable evidence anyway. I accept that it was for the jury to decide on reliability having considered the evidence of those in the chain of custody, but the Crown's witnesses were all vested in the outcome.
3. Julie Mugford, I believe, lied, but I also hold that her evidence is irrelevant, and in its critical aspects, amounts to hearsay and should have been excluded at trial as it was an attempt to unduly influence the jury.
4. It is just about plausible that Sheila did it without aid or involvement from Jeremy. It's at the very lower end of plausibility, and normally would not amount to 'reasonable doubt', but in this case it does due to the other points just outlined, especially 1.
5. There is no evidence that Sheila's body was moved by anyone other than the police.
Today, all those factors should lead to Jeremy Bamber's discharge from custody, though I believe he should be placed under psychiatric supervision as I find it more likely than not that he is the culprit. Points 1 and 2 mean the convictions are unsafe. Point 3 renders the convictions unsatisfactory and/or unsafe. You could argue point 4 was in the gift of the jury and they were entitled to dismiss Sheila-centric theories, but when you couple it with point 1, it looks like an unsafe conviction. Point 5 is also linked inextricably to point 1, but it also stands out as establishing reasonable doubt in its own right - hence, again, it's an unsafe conviction.
One thing that could change my mind about Bamber's culpability is if you can produce evidence that the 525 Model specification is other than how I say or the firing mechanism works in some other way.