Challenging Police DWI / DUI Investigations
Each citizen has protections against overzealous police that are guaranteed in the federal and state constitutions. If a police officer violates a constitutional protection, then the court may suppress all evidence gathered following the violation. The following is a list of some of these protections during a DWI / DUI investigation: 
A police officer cannot stop a motor vehicle without having a certain level of suspicion that a motor vehicle violation occurred or a crime has been committed.
- A police officer cannot detain an individual for investigation without having a certain level of suspicion.
- A police officer cannot seize evidence without having a warrant or there being an exception to the warrant requirement present.
- A police officer cannot arrest an individual without having a warrant or probable cause to believe that a crime has been committed.
- A police officer cannot search a motor vehicle without having a warrant or there being an exception to the warrant requirement present.
- Drivers cannot be stopped by a police roadblock unless the roadblock meets certain constitutional standards.
- When evidence is seized, the police must show a proper “chain of custody” for that evidence. An improper chain of custody may cause evidence to be disregarded by a court.
- Errors in a police report can be used to damage the credibility of the officer who wrote the report and other officers involved in an investigation.
- Mistakes in blood, urine, or breath testing procedures can be cause to have alleged evidence suppressed.
- Evidence that is destroyed or lost may be cause for a court to dismiss charges.
