Items that potentially contain sufficient amounts of DNA to obtain a profile are the most important evidence and the first priority to collect. However, the collection or swabbing of certain items may depend on whether or not residents are available to ask if these items are theirs, or if residents had the opportunity to talk to the responding investigator to indicate which items do or do not belong to them.
Examples of these items are as follows:
- Cigarette butts.
- Bottles, cans and drinking containers not used by the residents (collect the item and submit it to the lab if no liquid remains in the container or use one slightly moistened swab to sample around the mouth opening).
- Hairs found or caught in splintered wood or broken glass at the point of entry.
- Discarded latex gloves.
- Clothing items, bandannas, masks or hats that do not belong to the residents.
- Sunglasses or eyeglasses left behind by the suspect (collect the glasses and submit them to the lab or use one slightly moistened swab to sample the parts that rest on the ear, the bridge of the nose, and the bottoms of the frames that rest on the face underneath the eyes).
- Toothpicks, chewed gum, sunflower seed hulls, lollipop sticks.
- Cell phone left by the suspect (collect the item and submit to the lab, or use one slightly moistened swab to sample around the mouthpiece and a second slightly moistened swab to sample around the earpiece).
- Food items with bite marks — some food samples can degrade quickly at room temperature; sample the area around the bite mark with a slightly moistened swab at the scene (collect the food item and store it frozen).
- Evidence that might have semen on it (e.g., panties removed from a bedroom drawer and found crumpled up in another room).
Note: One alternate swabbing technique is to use a slightly moistened swab for collection, followed by a dry swab. Both swabs should be marked and may be packaged together.
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