A LONE female, asleep in a first floor bedroom wakes to find a male in her room who then sexually assaults her.
The offender leaves the bedroom through the open window and shins down the drainpipe to make his escape.
Crime scene investigators from Cheshire police attend the scene and speculatively swab the drainpipe for any traces of DNA the offender might have left behind.
The swabs are sent for super-sensitive low copy number DNA analysis and result in a partial male DNA profile.
That profile is searched against the National DNA database and a match to a local offender is made.
This is the sort of scenario ending in the kind of result which has just won CSI Cheshire high praise from a police watchdog body.
In its latest audit on the force’s forensic investigations department Her Majesty’s Inspectors of Constabulary awards it “good” to “excellent” grades in all areas, in terms of data quality and management arrangements.
The work of the team of specialists in the busy unit is as diverse as it is painstaking.
In just the past three months they examined more than 200 mobile phones – a process which can reveal evidence of anti-social behaviour from video files stored in them.
In the last six months the department’s photographic imaging unit has printed more than 40,000 pictures.
The crime scene investigators (CSIs) submitted over 3,000 CDs containing crime images to the department, which also photographed 1,333 fingerprint impressions from items submitted by the chemical treatment laboratory, and processed 96,729 negatives from road safety cameras. They attended 22 major crime scenes.
In the past year the fingerprint bureau has produced over 1,100 identifications from crime scenes.
The department’s electronic fingerprint scanning equipment has received and processed 11,500 prints, and the forensic footwear unit dealt with 1,159 crime scene marks in just four months.
Cheshire Police Authority chairman Peter Nurse said: “The work being done in Cheshire seems like science fiction but it is another example of the hidden world of policing which is funded by local taxpayers.
“It is vitally important that the authority is able to continue to fund this and other specialist areas of policing which are often hidden to the public.
He added: “Catching and securing the evidence to convict criminals is an expensive process. The authority continually looks for ways to make savings, by using in-house forensic specialists the constabulary saves £23,000 compared to the cost of using external companies but we need the continued support of the community to fund such excellent policing.”