For DUI blood test result to have any evidence value in court, a proper chain of custody must be kept.
How the Prosecution Lays Out the Chain of Custody
The prosecution must lay a proper foundation in order to admit blood test results in court. For a sample to be admissible, the prosecution bears the burden of establishing:
- Person who drew the blood
- Person who drew the blood was qualified to do so
- Time and location the sample taken
- Circumstances under which the sample obtained
- Laboratory technician who analyzed the sample
- Qualifications of the lab technician
- Sample accounted for the entire duration of testing
- Testing instrument of the sample analyzed on was properly calibrated and maintained
- Method of testing was an established method commonly accepted in the field
- Sample was properly preserved and stored prior to testing and during transport
Any time the blood sample changes hands, a document must be signed and dated, with the time of receipt acknowledged. This is to ensure that someone is responsible for sample at all times, to prevent chances of tampering with evidence. Some state statutes specify where blood sample is kept and stored during transport, as well as the timing requirements. If a sample doesn't comply with statute's procedures, the Judge may determine the BAC (Blood Alcohol Content) results inadmissible. Additionally, the prosecutor may even decide to dismiss the case.
Once arrested for DUI and subjected to blood draw, contact a DUI defense attorney in your state, city, or county. Failure of police to follow proper procedures may entitle you to suppression of BAC results and help in plea negotiations.