Forensic Evidence Analysis Summary

Evidence Handling and Analysis

• Liquid Dilution: Conduct liquid dilution if liquid evidence is present; ensure positive reports include references to the product tested.
• Soil Evidence: Soil samples must be refrigerated or frozen to prevent microbial degradation.

Fingerprint Analysis

• Comparative Processes: ACEV (Analysis, Comparison, Evaluation, Verification) is used for fingerprint comparison. Known prints are essential for matching suspects.
• Reverse Searches: Unsolved prints are run through reverse searches to identify potential matches.
• AFIS: The Automated Fingerprint Identification System (AFIS) uses state identifiers for tracking.

DNA Forensics

• Sample Collection: Ensure cleanliness by changing gloves to avoid cross-contamination when handling DNA. Samples are placed in labeled test tubes, marked with specific identifiers.
• Chemical Reagents: DTT and protein kinase are used for breaking down cells and deactivating harmful enzymes. The extraction process employs HTL buffer to isolate DNA from cells.

Print Development Techniques

• Super Glue Fuming: Utilized for developing latent prints on non-porous surfaces. This involves submerging objects in a chamber to capture fingerprints effectively.
• Ninhydrin Application: For developing prints on paper surfaces; typically set for 24 hours and then heated in an oven at 100°C.

Quality Control in Forensics

• Sample Processing: Samples must be centrifuged to separate components and ensure clarity. Different machines should be used for evidence and reference samples to reduce error rates.
• Quantitative Analysis: A thermomixer is used for controlling the temperature during processing, and quality control is essential after running the samples to ensure reliability in results.