According to one senior source familiar with the Surrey police investigation: "It can happen with abduction murders that the perpetrator will leave messages, asking the missing person to get in touch, as part of their efforts at concealment. We need those messages as evidence. Anybody who destroys that evidence is seriously interfering with the course of a police investigation."
The paper made little effort to conceal the hacking from its readers. On 14 April 2002 it published a story about a woman allegedly pretending to be Milly Dowler who had applied for a job with a recruitment agency: "It is thought the hoaxer even gave the agency Milly's real mobile number … the agency used the number to contact Milly when a job vacancy arose and left a message on her voicemail … it was on March 27, six days after Milly went missing, that the employment agency appears to have phoned her mobile."
The newspaper also made no effort to conceal its activity from Surrey police. After it had hacked the message from the recruitment agency on Milly's phone, the paper informed police about it.
It was Surrey detectives who established that the call was not intended for Milly Dowler. At the time, Surrey police suspected that phones belonging to detectives and to Milly's parents also were being targeted.
One of those who was involved in the original inquiry said: "We'd arrange landline calls. We didn't trust our mobiles."
However, they took no action against the News of the World, partly because their main focus was to find the missing schoolgirl and partly because this was only one example of tabloid misbehaviour. As one source close to the inquiry put it: "There was a hell of a lot of dirty stuff going on."
http://www.guardian.co.uk/uk/2011/jul/04/milly-dowler-voicemail-hacked-news-of-world
