There are many different ways to analyse the different types of evidence that can be collected at a crime scene. Different types of evidence require specific techniques to analyse them and produce a conclusion for an expert witness testimony to rely on in court.
Biological Evidence
Depending on the biological evidence that is collected, there are different presumptive tests that can be carried out to prove the identity of a substance that can then be sent to the lab for further analysis.
e.g. Blood - Kastle Meyer Reagent is used for the presumptive test of blood.
In this case, with the evidence collected, there was blood on the hatchet that killed Edward Evans but due to the time period and the lack of scientific procedures at a crime scene, the police had to rely on the witness statements of David Smith and Ian Brady and presumed from their statements that the blood was Evans'.
Chemical Evidence
There are various presumptive tests that can define the identity of different chemical substances such as GSR and drugs. Once a presumptive test has been carried out, the sample can be sent to the lab for further analysis to definitely identify the substance as sometimes, with a presumptive test, different substances can produce a false positive result.
e.g. Gun Shot Residue - Lead Nitrate and Sodium Rhodizonate are used for the presumptive test of GSR.
Physical Evidence
Physical evidence is not usually analysed in a laboratory as physical evidence can be items such as witness statements and surveillance such as CCTV and video recordings; however, some physical evidence can be analysed for traces of other evidence such as fingerprints on a weapon or on a video tape. In the case of the moors murders, there was physical evidence located in several locations such as the house that Hindley and Brady lived in on Wardle Brook Avenue and Central Manchester Train Station. Evidence found in these two locations is listed on the page of Procedures for Collection and Preservation of Evidence.
Evidence collected in the case of the Moors Murders was mainly Physical and Biological Evidence. The hatchet that killed Edward Evans could have been dusted for fingerprints to prove that it was Ian Brady that killed him. The blood also on the hatchet could have been tested to ensure that it was Evans' blood and rule out the possibility of another murder weapon. If the same crime had been committed in 2015, the evidence would have been analysed to ensure that the case is watertight and that there are no loop holes that could potentially ruin the credibility of the evidence in the case.
In the case of the Moors Murders, evidence that was collected at the scene would have been analysed depending on the type of evidence that it is. The bodies of the victims would have had a post mortem examination carried out to determine the cause of death and potentially find the murder weapon. The tape recording of Lesley Ann Downey's voice was listened to repeatedly to find traces of noise in the background that could lead to a time of year for when the sound was recorded (the police could date the tape because of a particular song playing in the background of the tape). The suitcases found at Manchester train station could have been dusted for fingerprints to prove that Brady and Hindley handled them. The blood on the axe that Brady murdered Edward Evans with could have kastle meyer reagent used on it to prove that it was human blood and further prove that it was Evans' blood by doing further tests in the lab. The name of John Kilbride written in Brady's notebook could have handwriting analysis carried out on it in the lab to prove that Brady wrote the name of the young boy and his victim.
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