I got a DUI/DWI but I wasn’t charged with the reason I was pulled over. Can my case be dismissed because of this?
No. Police officers have broad discretion when it comes to charging for offenses committed in their presence. They can charge you for every violation they see, charge some or one of the violations or they can decide to not charge at all.
In the case of DUI/DWI, police often see this as the most serious of the offenses they see and rather than charge for the traffic violation also, they will simply use their observations of the violation as evidence to support the DUI/DWI charge. It is important to note that the officer does need a reason to pull you over, ie, traffic violation, check point or accident investigation.
If there is not a legal justification for the police encounter, then your 4th Amendment right against unreasonable search and seizure might have been violated. This might be a defense for your DUI/DWI charge and could led to a dismissal.