Recent advances in canine genomics have allowed the development of highly distinguishing methods of analysis for both nuclear and mitochondrial DNA. We describe a laboratory exercise suitable for an undergraduate biochemistry course in which the polymerase chain reaction is used to amplify hypervariable regions of DNA from dog hair and saliva present at a "crime scene". Products are analyzed via gel electrophoresis to construct DNA profiles that implicate or exonerate dog owners under suspicion. (Contains 2 figures.)