Anthony Orchard QC, for Mick Philpott, asks Matt Lee: "Do you agree it's impossible to determine how petrol was introduced to the hall?"
Matt Lee replied :"Yes."
Anthony Orchard QC: "You're not able to say whether or not petrol was deposited through the letter box are you?"
Matt Lee: "No."
Prosecutor Richard Latham QC: "If petrol was deposited on the doorstep, what would you expect to find?"
Matt Lee replied: "I would have expected to find petrol on the concrete step."
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Speaking exclusively to ITV News, Dawn Bestwick said jail wasn't good enough for MIck Philpott and that "as a coward" he "deserved to die".
The events that eventually led to parents Mick and Mairead Philpott and friend Paul Mosley's conviction of manslaughter.