Immunohistochemical analysis of forensic evidence from a double homicide

We report the use of immunohistochemical staining for analysis of forensic evidence from a double homicide. A 38-year-old woman and her 7-year-old daughter were murdered by multiple blows to the head and face with a tomahawk, resulting in multiple fragments of brain tissue scattered about the murder scene. The victims' husband and father was the main suspect, who maintained that he was out of town on business during the evening of the murders. However, a shirt taken from the suspect's car on the morning after the murders (secured by the police before the suspect visited the murder scene) was found to have two small stains. DNA analysis on the stains showed the presence of the deceased wife's DNA, and immunohistochemical stains on shirt fragments conclusively documented the presence of deep central nervous system tissue, providing the critical piece of evidence needed to arrest and prosecute the suspect. This report demonstrates that shirt or similar cloth fragments can be processed into paraffin blocks and subsequently immunostained to search for and classify types of tissue fragments that may be present on the fabric.