You could still be convicted of a DWI without accurate breathalyzer results based off of field sobriety tests, video, officer testimony, etc., but blood alcohol levels cannot be used as evidence against you if there is a problem with the machine.
As far as you not being read your rights, anything you may have said after the arrest could not be used against you if you were never read your rights.
It sounds as if your case may have some procedural issues that need to be closely scrutinized by an attorney. Even if there is not much there to beat the charge, hiring attorney oftentimes can save you the fines and costs of any additional charges associated with the DWI.
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