Structuring cases into propositions, assumptions, and undisputed case information.

In this short publication we address the topic of evaluation of biological results given activity level propositions, particularly when the source of the biological material is not in question. When the issue regards the mechanisms or actions that led to the deposition of the biological material concerned, there is a need for more case information than when the issue pertains to the source of the DNA. It is up to the scientist to structure the provided case information into propositions, assumptions and undisputed case information. In our statements, deciding what goes in the propositions and what will be part of the paragraph dedicated to case information is partly personal. It may however affect the way we think about a case and thereby have consequences for the evaluation of the results as well as for the communication of the information to the recipient. In particular we highlight the importance of considering and communicating all DNA transfer mechanisms that are relevant to the evaluation under each proposition, and how the way the propositions are thought about (and expressed) can assist in this endeavour.