Four months ago a young mother who worked as a prostitute went missing.
Nearly two weeks later, the battered body of Rebecca Hall was discovered in an alley and police say they're disappointed by the response to appeals to help find the killer.
So how much impact did the fact that Rebecca was a prostitute have on public sympathy, and what difficulties do the police face in investigating such cases?
Martha is joined by Detective Chief Superintendent Brian Taylor and Hilary Kinnell, National Co-ordinator for Euro PAP UK. If you have any information about the Rebecca Hall case, please call the West Yorkshire police on freephone number 0800 318 001.
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