Collecting a Sample from a Smear
Collecting a sample from a smear is different from collecting from a thicker stain. Use the following procedure:
- Use a slightly moistened (with distilled water), sterile cotton swab and concentrate the substance on the tip of the swab.
- Collect a control sample by swabbing unstained adjacent surface areas with a sterile swab slightly moistened with distilled water.
- Use a slightly moistened swab and follow with a second dry swab for a perspiration smear.
- Allow the swabs to air-dry.
- Label and package evidentiary swabs and control swabs separately in envelopes or bindle paper.
Additional Online Courses
- What Every First Responding Officer Should Know About DNA Evidence
- Collecting DNA Evidence at Property Crime Scenes
- DNA – A Prosecutor’s Practice Notebook
- Crime Scene and DNA Basics
- Laboratory Safety Programs
- DNA Amplification
- Population Genetics and Statistics
- Non-STR DNA Markers: SNPs, Y-STRs, LCN and mtDNA
- Firearms Examiner Training
- Forensic DNA Education for Law Enforcement Decisionmakers
- What Every Investigator and Evidence Technician Should Know About DNA Evidence
- Principles of Forensic DNA for Officers of the Court
- Law 101: Legal Guide for the Forensic Expert
- Laboratory Orientation and Testing of Body Fluids and Tissues
- DNA Extraction and Quantitation
- STR Data Analysis and Interpretation
- Communication Skills, Report Writing, and Courtroom Testimony
- Español for Law Enforcement
- Amplified DNA Product Separation for Forensic Analysts