 The murder investigation , named Operation Green , was led by Sir Edward Crewe , Chief Constable of West Midlands Police , and included 100 police officers and 50 support staff from the West Midlands and West Mercia forces . Detectives viewed hundreds of hours of CCTV footage , gathered more than 100 separate exhibits and interviewed witnesses . Evidence was analysed by scientists from the Forensic Science Service ( FSS ) in Birmingham . Martin Whittaker , the scientist who headed the FSS team , spoke of the huge volume of evidence : " The team pulled together every strand of forensic evidence to create a kind of ' spider 's web ' and in the centre of it all ... was Philip Smith . In 20 years of working for the FSS , I have never had to deal with so much evidence in relation to one suspect . It was quite overwhelming . " 
