Looks like a bit of a cock-up on the policing front: http://www.bbc.co.uk/news/uk-england-coventry-warwickshire-36547161

Now, if I were a conspiracy theorist, this has all the hallmarks...

Prominent man under suspicion
Police dragging their feet
Suspect suddenly dies
Council leader tampers with evidence at body scene
Post-mortem inconclusive
Civil case against deceased ongoing

Agatha Christie could have a field day with this one

I didn't want to say, but it does seem a tad suspicious.