WHAT QUESTION(S) DO YOU NEED ANSWERED?
Which of the people in the motorway pile-up was driving?
Should the airbag have gone off?
Which side of the white line was the car on when the crash occurred?
What speed was it travelling?
What direction was it going?
How quickly or slowly did the driver react?
When did the pedestrian spot the bus?
When did the lorry load slip and roll it over?
Could collision have been avoided?
Were the headlamps working?
Did the seat belt pretensioner activate?
How did the coach fire start?
Was this a suspicious collision?
Does the technical evidence meet the test for corporate manslaughter?

TECHNIQUES :
A range of investigative processes and lines of enquiry can be involved:
scene examination, evidence gathering & interpretation (scuffs, scores, skids)
tachograph analysis
manual and computer-aided calculation;
filmed reconstruction and 3-D graphic visualisation
pedestrian and debris trajectory analysis
collision damage, energy, momentum balance, evidence transfer
correlation of collision evidence to injury
seat belt, airbag examination and electronic module analysis