The collision was one of the worst in living memory.
We launched a comprehensive investigation immediately after to establish the full circumstances which led to the collision.
Our investigation was meticulous and complex. We took hundreds of witness statements, examined 34 vehicles and consulted several experts, including meteorologists, pyrotechnic and forensic specialists.
Based on this evidence the Crown Prosecution Service took a decision to charge. However, following further consideration in recent weeks they have decided to discontinue the manslaughter charges.
More top news
Two people have died after being involved in separate lightning strikes in Wales' Brecon Beacons today.
Any lingering showers will ease this evening, to leave a dry night with plenty of clear spells. Minimum temperature 11 deg C (52 deg F).
Blackwood mother Trudy Jones was on holiday when she was gunned down in the Tunisian beach massacre that claimed the lives of 30 Britons.