Your diabetes can certainly affect your performance on field sobriety tests and even fool the breathalyzer. For an excellent discussion of this subject see the following Avvo guide (not my own): http://www.avvo.com/legal-guides/ugc/diabetes-and-the-counterfeit-dui.
Diabetes can affect your BAC levels. There are many sites on the web that can help with your research in this matter. I just looked it up and one site i particularly liked is posted below. Do some research to help with your question and consult an attorney who can explain how having diabetes can affect your BAC.
Indeed, diabetes can not only tamper with your BAC, it can also have an effect on how one performs on Field Sobriety Tests...see this article by Mr. Taylor for more information:
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