I have read the news reporting and I just don't understand how he came to be hit and for the result of that to be so terrible. Something in the reporting just does not add up and I could do with some normal person rather than a journalist to make sense of it for me.

I am a cyclist and I have a vested interest in knowing how to avoid deadly situations. In my experience to date accidents are always unexpected, however, with hindsight, so much could have been avoidable. Negligence is not always 100% one party or the other, even if it is 0.5% negligence on my side and 99.5% on the other side, there is still something in my control. There are easy wins like having a maintained bike, with lights, high-visibility clothing and no headphones being worn. There are also more subtle ones like confidence, not being deferential to motor cars and having pedal cleats correctly placed.

Was there anything that your friend could have done differently? Was there anything in the layout of the street that could have been different? What was the totally unexpected thing that other cyclists including myself need to add to their internal database of random hazards to look out for?

Given that this is police investigating police a considered and independent study of what actually happened could be of great use.