Criminal prosecutions rely on evidence in a court of law. Therefore in any case, well preserved, uncontaminated evidence is vital to uphold the law’s requirement for ‘proof beyond all reasonable doubt’. Consequently, the most vulnerable evidence is collected first. This is generally characterised by items that may be at the mercy of the elements – the wind may displace hair for example.

Fibres and hair are gathered using light sources which alter the contrast and highlight even the tiniest flecks of lint. These can then be transferred to a holding packet using tweezers. In interior locations carpets are vacuumed using separate virgin dust bags in every area. This material can then be sifted for vital trace evidence.

Fingerprints are photographed and dusted with powder which sticks to any oily deposits and reveals the print’s spiral pattern. A copy of the print can then be taken by using a special lifting tape. These transparent strips are placed over the print momentarily before being peeled off to give CSIs an exact reproduction of the fingerprint to take back to the lab.

All evidence is packaged separately and hermetically sealed to safeguard it from cross contamination.