A lawyer for the police said he was worried about "sensationalising" the inquest with a live demonstration of the bag and offers a video clip by an expert as alternative.
Police reveal "problems in the DNA analysis" of mixed profile found on Williams' hand - found the contamination was from scientist at scene.
The error was spotted by a scientist who's evidence helped convict the killers of Stephen Lawrence in January. The coroner wants to hear from her.
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Police say they have traced four drivers who are thought to have hit the woman, and added that a fifth vehicle may also have been involved.
Police are trying to trace two men after two homophobic attacks on gay men in Walthamstow
Two London Boroughs make it into the top 15 places to live in the UK.