In this interview, you will find out how to tackle splashing incidents directly from our very own IFI DNA Analysts. You will want to read this!

Q: Tell us about the work IFI does on “splashing” cases

A: Liz Kopitke, IFI DNA Technical Leader, explains.. , “IFI has a contract to provide testing and expert witness services to a large urban corrections department in support of their investigations into “splashing” offenses—incidents where an inmate assaults a staff member with an unknown liquid or substance. We attempt to determine if that liquid/substance contained a body fluid (blood, saliva, semen, urine, and/or feces), via laboratory testing.

Q: What kind of samples do you most frequently deal with?

A: For splashing incidents, the most common items received are officer clothing (uniform shirts, pants) that have been splashed with an unknown liquid substance.

Q: Can you describe the protocol you follow?

A: All items undergo biological screening, beginning with visual observations of the item(s) followed by examination with an alternative light source. For visible and/or fluorescent stains consistent with the described event, our standard stain identification procedures are used. For items (usually dark blue or black fabric) with no visible or fluorescent staining consistent with the event description, we have adopted a urine testing procedure adapted from ecological quadrat sampling methodology. A candidate testing area is identified based on the incident description and any relevant visual observations of the item. Cuttings are taken to intensively sample approximately 2% of the total candidate area, then the remaining candidate area between cuttings is wetted with a mild detergent solution and sampled with a cotton swab. Swabbing the fabric is less sensitive than cutting, but in the absence of focal stains, allows sampling of a larger square area.

Q: Is there a specific case that you remember the most?

A: Forensic DNA Analyst, Caitlin Hoey: “I remember a case in which the incident was described as an inmate urinating directly onto an officer’s pants. The incident had occurred approximately 10 months prior to the sampling and testing of the item, but there were visible stains on the pant leg consistent with the description. These visible stains were sampled and produced a positive result on RSID-Urine. This 10-month interval is thus far the longest between incident and testing for which a positive result has been produced in our corrections casework.”

Q: Is there a specific case you disliked the most? What made it so?

A: Shelby Carlson, Forensic DNA Analyst, “There are cases received in which the incident involves an officer being hit with multiple liquids by multiple inmates. In one case, there were visible stains on the item outside the area that described. In this scenario, both the visible stains outside of the described area and any potential non-visible stains in the described area needed to be considered when sampling, as the officer was struck with multiple liquids whose appearances may differ on the material. Cases like these are difficult in that they can vastly increase the number of samples taken from an item, as well as increase the number of fluids considered.

What are some of the challenges you face as a Forensic Scientist dealing with splashing samples?

The major challenge is sampling items that do not have any visible or fluorescent staining, as the description of the event must be heavily relied upon to identify a candidate area for testing. As mentioned previously, there are also scenarios in which stains on the item are inconsistent with the described splashing area, resulting in multiple areas to be considered for testing. In many cases, there are items that may have several stains across the garment that are inconsistent with one another. Again, the description of event and the physical properties of all the stains must be considered to determine which ones are probative of the incident described and for which fluid(s) they should be tested.

Do you have any other suggestions and/or advice for lab personnel out there using RSID products to test splashing evidence?

Encourage your submitting agencies to be as specific as possible regarding the area of the item that was splashed, as urine stains in particular are extremely difficult to locate on dark fabrics. Additionally, minimize the post-incident testing interval as much as possible. Urine composition is variable both between individuals and between multiple voids from a single individual, and signal from stains can diminish over time.