Once an officer decides to make an arrest, intervening rarely changes it and can itself result in your arrest. Speech alone is a recognized defense.
These cases usually involve someone trying to stop a friend or loved one from being arrested. Most are well-intentioned people asking questions and trying to talk the officer out of it.
The problem is that once an officer has decided to make an arrest, it is rare that anyone talks them out of it, and stepping between the officer and your loved one is itself an offense you can be arrested for. There is a defense in the statute if the interference consisted of speech only, which is often where the defense of these cases begins.
Citation: Texas Penal Code §38.15, Interference with Public Duties
Degree and classification: Class B misdemeanor.
Statutory language: A person commits an offense if, with criminal negligence, they interrupt, disrupt, impede, or otherwise interfere with a peace officer, EMS or fire personnel, or other listed public servants performing their duties. There is a defense if the interference consisted of speech only.