A Drink Driving Case: Missing signature


In a drink driving case, one of the first pieces of evidence that should be disclosed is the lengthy document completed by the police at the police station.

This document, known as the MGDDA form, contains the procedure adopted by the police when completing the breath test. Additional documents, known as the MGDDB and MGDDC forms will need to be completed if urine or blood samples are requested. All these documents, many pages long, are designed as an ‘idiots guide’ to avoid the police making mistakes. Idiot proof.


The end of the MGDDA form contains a section requiring a signature from the officer completing the breath procedure. In a recent case, the signature was missing.

Another important signature can be found on the printout from the breathalyser machine. The printout gives the results of the breath test. It confirms that the machine was calibrated, provided two correct ‘tests’ and provided two correct samples. Importantly, it contains a clause and it must be signed. In two out of my last three cases I have been provided with an unsigned printout! See one of the printouts above – note the lack of signature.