i am NOT going to comment on this case as other than what i have read here i, i have no knowledge of it - but placing significance on things ,even such as physical evidence is , er tricky ,to say the best and measurable ?? - depends on the context .
for example : ( going to use some fire service analogies here ) say for instance you where called to a building that was "well alight " ( eg going well ) - there is no one trapped - and no danger to other buildings or people - and the building is isolated from others but in a residential area , so you look at the building and start looking for reasons - collecting "clues " to what had happened .
so lets take our hypothetical building - a standard 2 up 2 down brick built dwelling - with no gas ( only electric ) - unoccupied at the time of your arrival .
so initial appraisal : you have taken 3 minutes to arrive - witnesses say that the building "exploded " in to flame - significance ?? - well buildings only usually do this with the aid of an accelerant ( as far as i know there have been no cases of "spontaneous combustion " of normal houses ) so clue number one ??
the fire has spread to all floors and the roof - you know that the call and time to arrive was a total of say 5 minutes - based on your knowledge of the mechanics of "normal " fire spread you also know that this fire has developed WAY too quickly -even allowing for say 5-10 minutes for the fire to be noticed - clue number two - significance ??
during the operation to tackle the fire - one of you men reports the find of two empty petrol cans lying in the garden - significance ??
amongst the crowd of onlookers you spot a well known local arsonist ,watching proceedings - significance ??
the owner of the building turns up and seems a little too calm for someone whose house is burning down - significance ??
his children are with him and are looking frightened - significance ??
the owner is in deep financial trouble and about to go bankrupt -significance ??
the mans wife left him a few weeks ago - following a major row - significance ??
OK i wont take this any further for now - have a think about each of these things and draw a conclusion - i appreciate you may not have any knowledge of firefighting and investigation so i have made this one fairly easy for you - but what i would like you to do is rate ,from one to ten each of these and give your reasons for your marks
this is actually based on a true scenario - so i know the answer

any one want to take a stab at it ??