Lancaster was already seeing a multiyear decline in crime before the birds, says Robert Jonsen, captain of the Lancaster Sheriff Station.

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Ms Lancaster was attacked in a park in Bacup, Lancashire along with her boyfriend Robert Maltby, because of the way they were dressed.

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Ryan Herbert and Brendan Harris, both from Bacup, were jailed for life in 2008 for Miss Lancaster's murder, and for causing grievous bodily harm to her boyfriend Robert Maltby.

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