The fingerprints may not have been in blood

In the retrial the defence put up a good argument that the fingerprints on the top of the rifle, in the pickup position were not in blood.  It appears that Kim Jones, the expert who made the determination that it was blood, only assumed it was blood and he made some incorrect observations about what polilight does in contact with it.  If this is true, then it helps understand how the glasses didn't get blood on them.

It would appear that the glasses came off soon in the fight with Stephen.  Possibly David trod on them during the fight, damaging them badly as well as alerting him to their location on the floor.  He may have had time to kick them away to prevent further damage, knowing that he would still need them to kill Arawa.  It makes sense that he would not remove the gloves until after Stephen had been subdued by strangulation or loss of blood.  Then he would remove them, because now they were bloody and would put blood on everything he touched, including the rifle.  Once the gloves were removed there would be no further need to touch Stephen and therefore he could keep his hands blood free.  He then picks up the rifle, leaving the fingerprints that Jones identified and gives Stephen his fatal shot.  After this is done he retrieves his glasses, and since his hands are blood free, there is no blood to transfer onto them.  He then takes them to his room to assert whether or not they are of any use to him, but on the way hears Laniet gurgling and goes in to finish her off.  Once in his room he finds that the lens is missing and they are too broken.  While in his room he takes the opportunity to reload a magazine.

It is quite possible that Arawa was woken by the tumult upstairs and was making her way up the stairs by the time David appeared.  He would then shunt her back down to her room where her body was found executed on the floor.

Comments

Probably reading too much

Probably reading too much into this. Remember the blood on the light switches - so his bare hands must have been blood stained. Also the gun was covered in blood after the fight - and we know he continued to handle it long after the gloves had been disposed of.

Also he handled the bloody gun with clean hands (post paper run) when Robin was shot.  Of course Karam would argue that Robin shot himself but then he suggested David picked up the rifle when he 'discovered' his dead father.

The fingerprints on the rifle evidence can be interpreted in many ways -- but the correct interpretation is pretty obvious in my opinion.

Fingerprints in blood ,etc.

There was blood smeared over the rifle which means it was wiped when there was blood on it. Those fingerprints may not have been in the pick-up position. From tests I have done I believe those prints could have been made using a reverse grip with the left hand while wiping the rifle down, thus smearing it with blood , using the right hand.  I believe those gloves could have been used to wipe the rifle down as they are very bloody.
But I would need to see the actual rifle to check if my theory is valid.
It is possible that David Bain gripped the rifle where there was no blood on it.
However Kim Jones is a fingerprint expert and he was sure he saw blood where those fingerprints were . He believed they were positive prints meaning that David Bain had blood on his fingers when he placed them on the rifle.
In the Bain/Binnie interview Bain's best notion was that it was animal blood from the summer.
So far as the glasses and lenses are concerned.
An expert said that the frame would have been bent when it was forced against either a mattress or carpet. I would suggest the carpet because there was a great deal of blood on the bed.  Both lenses would have fallen out . Neither lens could have been replaced in the frame.
At some point of time David Bain must have picked up the frame and one lens.
When he did that the hand he used must have been free of blood. I don't know how he missed the other lens because a photo or video shows that lens in the open, but close to that ice skating boot, when Stephen's body was in the room.
The police had some difficulty removing Stephen's body from the room and it is possible one police officer's foot could have slipped and in doing so pushed that lens a few centimetres causing it to end up under the toe of that ice skating boot.
At some point David Bain took those glasses to his room, but not before he had shot Arawa. Those bloody sockprints leave a trial from Margaret's room to the top of the stairs so it is obvious that David Bain went downstairs before going back to his room.

Apparently the towel that was

Apparently the towel that was found in the bathroom had some of Robin's blood on it.  One has to wonder how that got to be given that David had no need to touch Robin and therefore get bloody, unless there was some errant splatter on David.

Having had glasses most of my life, I can vouch that the only times I have broken them is when they have been trodden on.  Glasses do not break when falling on the ground, although a lense may fall out.

The whole position of the lense controversy is a bit too complicated for any easy conclusions.

Arawa shooting

Maybe Arawa wasn't woken by the commotion upstairs. Maybe she was already dead. Perhaps she was shot first but woke only when there was a click and a misfeed as David approached and jumped out of bed to confont him. With her out of the way there was no rush to get back downstairs apart from showering and washing up. Steven was perhaps the last big hurdle before the paper run? 

Arawa last of four.

The police seem to be sure that Arawa was the last of four, and the defence accept that also.
The Crown Prosecutor at the first trial said " The sequence of events will never be known exactly . But we know the mother preceded Stephen and we know Arawa was the last of four. Whether Laniet was shot first or the mother we may never know."

Animal blood? Not blood? Human blood?

I recall a clip on TV news while the retrial was in progress where the prosecutor had a dig at the defence's changing position on those prints.  They were human blood prints, then rabbit blood and then at other times not blood at all.  I may have the sequence wrong but they went for all scenarios at least once.

Kent I guess we will never

Kent I guess we will never know all the facts as Karam won’t let David confess and tell all. But as far as David's pristine prints on the rifle go I am of the opinion that they were in blood, after all a blood sample was taken right beside one of the fingers “so as to not disturb the print itself” and that sample when tested proved to be of human origin the same as the other samples from other parts of the rifle. That is good enough for me.
 
 
As for the glasses coming off if you were to punch yourself in the side of the face where David had a bruise you would strike the frame of the glasses and they would possibly bend and fall off possibly with a lens becoming dislodged, as for no blood on the glasses and one lens found in David's room, there may have not been any blood splashed on them or he may have just washed them when he washed all the blood off his hands and body in the shower or hand basin.

Blood, no blood and lenses.

The London ex detective Carl Lloyd said there was no blood under those fingerprints.
The Crown Prosecutor asked him if he was not aware that the defence case was that it was rabbit or possum blood. Lloyd said he didn't know what a possum was, but that there was definitely no blood under those fingerprints.
Kim Jones came back the next day and said he had carried out more tests using his own blood and that proved that Lloyd was wrong.
There was a problem with the link and Lloyd said he couldn't see anything clearly on his screen when the Crown tried to point out where he had gone wrong.
David Bain told Binnie his best notion was that it was animal blood dating back to the summer.
Re the lenses. Both lenses had dust on them so neither would have been washed. There was verdigris on the frame. 
The expert said the frame would probably have been bent by being forced into either a mattress or carpet, causing both lenses to pop out.

  

Did David Bain have a shower?

Going by what he told Binnie he must have.
He told Binnie the reason why he didn't take his mother that cup of tea, sorry, coffee,was because he was all sweaty and dirty.
There was no dirt on him when the police arrived so he must have had a shower.

As a glasses wearer myself, I

As a glasses wearer myself, I can tell you there is not much significance in dust on the lenses.  Dust settles easily and a lot of dust has to collect before vision is impeded.  Karam claims that the dust suggests that the glasses had not been used and it disproves the police theory that David wore them.  At the same time he berates the house for being a tip, which at the same time would generate more dust than the average house.  All inhabitants of the house would have had a higher tolerance of dirty cups, dirty windows, and dusty glasses lenses than most.

The funny thing is Kent Wear

The funny thing is Kent Wear asked the optician Sanderson whether the glass lens atracted dust and Sanderson answered yes, in a hous like the Bains you would have dust on a pair of glasses sitting around in a matter of hours I would think especially as dust would be stired up in the fight.

In my experience if you hit

In my experience if you hit someone with glasses on, they seldom break.  A lense may come out, but most damage is done in contact with the floor, either through falling or being trodden on.  The reason I wrote this post is because if David trod on the glasses, then that would give him awareness of where they were in the room, and cause them damage.  He would then have a sense of where they were so he could pick them up later.

Damaged glasses frame.

Kent, have you ever wrestled with someone on the floor when you were wearing your glasses?
Have you ever had your head pushed into the carpet when you were wearing your glasses?

Robin's blood on towel.

I have given this matter considerable thought and my best notion is that Robin wiped his hands on the towel when he had blood on them.
While the abrasions on his hands were insignificant one or two of them may have bled. When I get a scratch from a rose thorn my arm or hand will bleed quite profusely. Robin may have had an abrasion that was only minor but that bled profusely. So he would have washed his hand and then tried to stop the bleeding by using that towel.
In my case I would use a flannel.

Robins blood

David would have had some blood splatter on him from the close quarters shooting of Robin, most likely on his hands which were closest, or his face. When David wiped his hands and face on the towel the blood would be transfered. 

The glasses were hardly

The glasses were hardly damaged at all if you check the pics, but the lens did pop out.

Lenses

My understanding is that both lenses had popped out.