Explain How Evidence is Processed

Sure, here’s the information arranged into sections:

Collection and Preservation of Evidence

Secure the scene: Initially, the crime scene is secured by law enforcement officers to prevent contamination. This is where initial evidence collection begins.
Systematic search for evidence: Police and crime scene investigators conduct a thorough and systematic search of the crime scene to collect evidence.
Preservation of evidence: Once identified, the evidence is carefully collected and preserved to prevent degradation or contamination. Everything from blood samples to weapon fragments is handled with extreme care.

Examination and Analysis of Evidence

Preliminary examination: At the laboratory, each piece of evidence undergoes a preliminary examination. This helps to determine which specific tests or examinations should be conducted on the evidence.
Analytical procedures: Laboratory technicians and scientists then use various analytical techniques, depending on the type of evidence. Examples include DNA analysis, fingerprinting, blood spatter analysis or ballistics.
Interpretation: In this stage, the scientific experts interpret the results. This could involve linking a suspect to a crime scene or identifying a substance as being a particular type of drug.

Documentation and Report Writing

Record keeping: Strict record keeping is essential throughout the entire process of evidence handling. This includes documenting each piece of evidence and its source, who handled it, and when and what procedures were carried out.
Written report: The forensic scientist prepares a written report of their findings. This report should include all methods used, their results, and any conclusions drawn.
Testimony in court: Experts may also present their findings in court. The evidence, no matter how scientifically sound, must be explained to a lay audience, i.e., the judge and jury.

Always remember the principle of chain of custody - a legal term referring to the unbroken trail of accountability that ensures the physical security of evidence from collection through to courtroom presentation.