Blood Results Michigan Accident - Hospital Blood Draw - Whole vs Serum Blood - What's the difference for a DUI case in Michigan?

When arrested for a DUI in Michigan, the police can pick from three different chemical tests; blood, urine or breath. A blood test can vary depending upon the purpose of the initial blood draw. When the blood is drawn, it could either be calculated as whole or serum blood. This is dangerous proposition for a client, because serum blood will come back at a higher BAC than whole blood. A conversion must be done in order to get an accurate result. The law requires that serum blood be converted to a whole blood equivalent.

The blood is usually serum when drawn for medical purposes, which is analyzed at the hospital rather than a criminal case, which is analyzed at a forensic laboratory; the blood will be serum if the blood is drawn to begin for purposes of a criminal case. A hospital uses an enzymatic method that tests blood serum; whole blood in comparison contains cellular material and proteins that clot.

The difference in process comes down to hospitals will centrifugate whole blood, which means spinning it, which eliminates solids and leaves only a serum, which is a higher concentration, which results in a higher BAC level. Serum blood can contain 1.6 more alcohol than whole blood, which could turn a 0.07 to a 0.11, which is a major difference when working on a DUI case in Michigan.

Any blood result attributed to my client in a Michigan DUI case is first examined to make sure we’re working with the whole blood number, and not an elevated serum number. Sometimes this requires contacting the hospital to obtain the documentation that occupied the blood result.

I run into these sort of issues in accident cases where my client is rushed to the hospital for medical purposes, examined, treated and cared for, but not investigated and charged until the “medical” portion of the case is over. The hospital draws blood as part of their process, but not to prosecute, but rather to treat. Sometimes we need to convert this in order to protect my client from being prosecuted with an unfairly elevated number.