Chain of custody is an important element to any investigation. Chain of custody establishes that the evidence presented is the same evidence that was collected and has not been tampered with. This requires sufficient documentation to establish who had access to the evidence, when, and where it was being stored. Lately I have been seeing less and less chain of custody information provided by the State, especially in blood draw DUIs. 

Chain of custody is necessary for authentication and identification:

1. The individual blood sample was taken from the Defendant;
2. It is the same sample taken in relation to this case;
3. It was properly handled and transported in accordance with lab policy and procedure;
4. It was not contaminated in some way;
5. It is the sample connected to the blood toxicology test and results.

 Without sufficient chain of custody documentation the evidence is inadmissible.