Nicola Bulley: Why can it take so long to find bodies?
By Dominic Casciani
A question many have been asking is - could she have been found sooner?
Without getting into scientific detail that some may find distressing, bodies do not stay in one position at the bottom of water, near where they were last seen.
Over time they will resurface, unless they have become completely lodged in an unreachable underwater location.
There has been a lot of focus on Peter Faulding, the private search contractor who works with police forces around the UK.
Crucially, Mr Faulding says sonar would never be used to search reeds by the side of a river because it would not penetrate them.
Such a search would have to be manual riverbank and wading search.
"My previous comments saying that if Nicola was in the river, I would find her, still stand," the forensic search expert said.
We do not know if the police or any other team carried out that manual search of the critical area or had been tasked to.
And it is not clear whether Lancashire Police considered other technologies.
The science, skills and practice of finding bodies in water shows it is one of the toughest challenges in policing.
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