Probable Cause

 Originally posted on the website of our contributors, Law Office of Bryan Fagan.

Handling a decent number of criminal cases at my firm at any given time, the first thing that I usually look at when someone accused of a crime comes to my office for a FREE CONSULTATION is whether probable cause existed for the arrest. But while I know what probable cause is (although based on some of the cases I’ve witnessed pass the probable cause standard, I doubt whether I even know what it is anymore), most clients that come to my office don’t even know about probable cause and what it is.

What is probable cause:

Probable cause is the constitutional requirement of an officer before being able to arrest someone for a crime, or to search his person or property (searches will be discussed in another article). The term derives from the 4th amendment of the Unites States constitution which provides the:

“right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.”

What the term means in plain terms is basically an officer must have sufficient evidence or reason to believe that a crime probably occurred before being able to arrest a person or before getting a warrant to search a person’s property.

Reasonable suspicious different than probable cause:

 Reasonable suspicion is the standard required before an officer can detain and question an individual about a crime. The standard for questioning under this rule is lower than the probable cause standard, and no evidence is required to be present for the questioning to occur other than a “reasonable suspicion” that either a crime has occurred or may be happening. Keep in mind that being “arrested” and “detained” are two different things. An arrest is when someone is in handcuffs and generally is being charged with a crime and on the way to jail; or when someone is in police custody. Detaining someone is keeping a person detained for a short time that would allow an officer to question the person involved or waiting for a K-9 unit to arrive.

Being arrested and being detained are different

Exception to the probable cause requirement:

There is an exception to the probable cause requirement where an officer is under the mistaken belief that a valid warrant for the arrest of the person exists; but in reality a valid warrant does not exist as the result of a mistake made by court employees. For this exception to apply, the officer must have acted in good faith in his/her belief that a valid warrant existed. Hence, probable cause is not required when there is already an existing warrant for the arrest of a person, which still requires probable cause to be issued, but does not have to be at the time of the arrest.

What happens when you are arrested without probable cause?

An arrest without probable cause makes the arrest or any subsequent search illegal and the prosecutors or the court will need to dismiss the case. As promised in my Miranda Rights article, a follow up article will be provided soon regarding the validity of a “search”.

 Final words:

It is extremely important to look at the details of an arrest, or the validity of an arrest warrant, to ensure that probable cause existed in criminal charges. This is one of the best ways to get a case dismissed without the hassles of going through the different stages of a case including trial.

Contact Us 

If you are looking for a criminal defense attorney and want to know what to know more about probable cause, what strategy to take in fighting your allegations, or if you simply want to call to discuss your legal issue, call or email me, Amir Tavakkoli, Houston attorney from the A.T. Law Firm. Our phone number is 832-800-5590 and the email is We also travel to different counties including but not limited to Harris County, Montgomery County, Liberty County, Chambers County, Galveston County, Ford Bend County, Waller County, and Brazoria. Contact the A.T. Law Firm by calling (832) 800-5590 for a free consultation.