Challenging the accuracy of a breathalyzer or blood test can be a complex process, but it is possible to question the results if you believe they are inaccurate. Here are a few steps you can take:

1. Educate yourself: Understand the science behind breathalyzer and blood tests. Familiarize yourself with the factors that can affect their accuracy, such as calibration, maintenance, and potential sources of error.
2. Consult an attorney: Seek legal advice from a professional experienced in DUI cases. They can guide you through the specific legal procedures and requirements in your jurisdiction.
3. Request the documentation: Obtain the records related to the breathalyzer or blood test, including the operator's training records, maintenance logs, and calibration certificates. These documents can help identify any potential issues.
4. Examine the test procedure: Review the specific procedures followed during the test. Look for any deviations from established protocols, as they may impact the accuracy of the results.
5. Challenge the equipment: If you suspect the breathalyzer device was faulty, you can investigate its reliability. Research the specific model used, check for any known issues or recalls, and gather evidence to support your claim.
6. Question the blood test: If you believe the blood test results are inaccurate, you can question the sample collection, handling, and analysis processes. For example, you may want to investigate whether the blood sample was contaminated or improperly stored.
7. Consider expert testimony: In some cases, it may be beneficial to consult an independent expert to evaluate the breathalyzer or blood test results. Their expertise can provide valuable insights and support your challenge.

Remember, the specific steps and requirements may vary depending on your jurisdiction and the circumstances of your case. It's crucial to consult with legal professionals who can provide tailored advice based on your situation.

For more information, you may find the following resources helpful:

• National Highway Traffic Safety Administration (NHTSA)
• American Civil Liberties Union (ACLU)
• Cornell Law School - Driving Under the Influence (DUI)