Defenses to DUI and DWI Charges In Chester County, PA

Being charged with a DUI in Pennsylvania can be a frightening experience. If you are facing DUI charges, you might be scared about the consequences you might face.

While the penalties for DUIs in Pennsylvania are severe, it is possible to defend against your charges with the help of an experienced West Chester DUI lawyer at DiCindio Law.

When you meet with your attorney, your lawyer will carefully review the police reports, video, lab reports, and other evidence to identify the potential defenses that might be available to you. Some common defenses to DUI charges are described below.

Common types of defenses to DUI charges

The particular defenses that you might raise to a DUI charge will depend on the facts and circumstances of your stop, investigation, search, and arrest. Your West Chester DUI lawyer will determine the best defense strategies to use to secure the most favorable outcome possible in your case.

  1. Absence of impairment

Under 75 Pa.C.S. 3802(a)(1), you can be charged with a DUI when an officer believes you have ingested enough alcohol that your driving is impaired. While the state’s DUI per se limit is 0.08%, this subsection means that you can be charged with a DUI even when you have less alcohol in your system. An officer might arrest you and charge you with a DUI even when you are not impaired based on his or her observations of you.


For example, an officer might believe that you are under the influence of alcohol when your eyes appear bloodshot and your face is flushed. He or she might also arrest you if you appear unsteady on your feet or show indicators on a horizontal gaze nystagmus test. However, these types of observations might be explained by medical conditions, including musculoskeletal disorders, allergies, conjunctivitis, inner ear problems, glaucoma, and others.

If you submitted to a breathalyzer test that returns a result showing that you had not drunk anything or that your BAC level was much lower than 0.08%, your attorney can present evidence showing that the officer’s observations of you can be explained away by other conditions you might have.

  1. Unconstitutional stop

Officers cannot randomly pull people over unless they have set up a DUI checkpoint and operate it correctly. Otherwise, an officer must have a reasonable and articulable suspicion that you have committed a traffic offense or a crime before he or she can stop your vehicle.

If your attorney determines that the officer had no reasonable suspicion to support the stop of your vehicle, your lawyer can file a motion to challenge it in court. If this type of motion is successful, all of the evidence the police gathered as a result of the stop will not be admissible against you. This would mean that the prosecutor would likely be forced to dismiss your case.

  1. Lack of probable cause

Before an officer can arrest you and charge you with a DUI, he or she must first have probable cause to believe that you are under the influence.

Officers try to build probable cause through their observations of you during your traffic stop. If the officer did not have enough evidence to support a probable cause finding, your attorney can challenge your arrest in court.

If successful, all of the evidence the police gathered after your arrest would be inadmissible, including your post-arrest breath or blood testing. This could result in a dismissal of your charges or a plea to a lesser offense.

  1. Improper DUI checkpoint

While DUI checkpoints are legal in Pennsylvania, they must be set up and operated according to specific guidelines and standards. Police must notify the public of the checkpoint in advance and must set it up in an area where intoxicated drivers are known to be. The checkpoint’s location cannot be changed once it has been agreed upon.

Police must also use a pre-determined system for stopping vehicles going through the checkpoint instead of randomly stopping people they believe look suspicious. If you were arrested at a DUI checkpoint, your attorney will carefully examine whether it was set up and operated correctly or if you can challenge it.

  1. Improper chemical test administration

Breath and blood tests are not infallible and are instead subject to administrator errors. The equipment must be certified and properly maintained to provide reliable results.

The test administrator must also have current certification to administer the tests and must follow specific protocols. If your attorney finds that the machine was not calibrated correctly or was not properly maintained, your breath or blood test results can be challenged.

Your results can also be challenged if the administrator failed to follow proper protocols. Finally, if you had a blood test, your attorney might review how the sample was collected, stored, and sent to the lab. If there were any mistakes made or if the chain of custody cannot be established, your blood test results might be inadmissible.

  1. Wrong person

The prosecutor must prove that you were the person behind the wheel to convict you of a DUI. If the police arrived after you and others exited your vehicle and did not see who was driving, your attorney might challenge your DUI charge by calling witnesses and presenting evidence that you were not the person operating the vehicle.

  1. Improper SFST administration

Police ask people to submit to standardized field sobriety tests when they suspect that they might be under the influence of alcohol. You have the right to refuse to submit to these tests at the roadside. However, if you do submit to them, your attorney will review the video to see whether the police administered them properly. This can help your attorney to cross-examine the arresting officer in court and point out errors that he or she made.

Contact Our DUI Law Firm in West Chester, PA

If you are facing criminal charges and need legal help, contact the West Chester, PA DUI lawyers at DiCindioLaw, LLC to schedule a free initial consultation.

DiCindio Law, LLC

29 S Walnut St
West Chester, PA 19382
(610) 430-3535


***This blog article is made available by the law firm publisher for educational purposes and to provide general information, not to provide specific legal advice. By reading, you understand that there is no attorney-client relationship between you and the publisher. The above-listed information does not include the entire criminal code, annotations, amendments, or any recent changes that may be relevant. The information provided is for informational purposes only and may not reflect the most current legal developments. These materials are not intended, and should not be taken, as legal advice on any particular set of facts or circumstances. Please contact DiCindio Law, LLC for a consultation and to discuss what law is relevant to your case.***