What is Probable Cause? | Fourth Amendment

The recent epidemic of police violence aroused my interest in the law. My interest peaked when I noted specific instances of police officers making medical decisions. In reviewing the law, in particular, probable cause, I found nothing granting law enforcement medical licensure or the right to practice medicine. Therefore, I went deeper into what probable cause is and the Fourth Amendment, which has been forgotten in the midst of justifications for multiple warrants, police violence, and murders, as well as unlawful detention of innocent people.

What is probable cause?

Probable cause is the the burden of proof police officers and courts must demonstrate to make an arrest. Judges sign arrest warrants before an arrest, but often do so within 48 hours after the arrest to prevent unreasonable delay and not be in violation of the Fourth Amendment.

Probable cause is based on suspicion that an accused person is more likely to have committed a stated crime based on information gathered. Videos suggest there is no information gathering, and police officers have overstepped their bounds tremendously. Law Enforcement no longer abides by the rules of the law or the Constitution.

The following images around the web suggest police often have no probable cause for many arrests and also document their excessive use of force. More often than not, this force is violent, and it causes irreparable physical harm, mental disabilities, and even death.

Law enforcement professionals are violating Americans’ Constitutional rights. At minimum, they have opened themselves up to additional liability by making medical decisions. So, why is there not more outrage being expressed by our politicians? Where are the checks and balances of American government—the lifestyle that we arrogantly ram down the world’s throat?

There are many cases in which families seeking help for their loved ones who struggle with mental illness end up seeing those loved ones incarcerated or murdered by local police on arrival to the scene.

What probably cause existed  for this officer to repeatedly punch this middle age woman in the face?  Or taser a baby? Or murder Eric Garner? Or repeatedly shoot and murder an acutely suicidal unarmed teenager? Or shoot Mike Brown when his hands were in th air?




Fourth Amendment

All the activities in this section are based on the Fourth Amendment.”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.” Fourth Amendment, U.S. Constitution



What is a probable cause hearing?

Justification for Arrest

The Fourth Amendment requires courts to confirm that an arrest is supported by probable cause either before or shortly after officers take a suspect into custody. A judge or magistrate’s signing an arrest warrant serves this purpose, but most arrests don’t involve warrants.

No Unreasonable Delay

As a general rule, a probable cause determination within 48 hours of arrest satisfies the Fourth Amendment. (County of Riverside v. McLaughlin, 500 U.S. 44 (1991).)

of an arrests, if not the fourth amendment was violated.


Investigating rape crimes, Part 2: Evidence collection and analysis


However, even if investigators know the victim’s assailant and make an arrest shortly after the crime based on probable cause, it’s still critical all evidence protocols described in this article be followed. Arrest only requires probable cause. Conviction in court requires a much higher standard: proof beyond a reasonable doubt. Experienced investigators know the variables under which an arrest is initially made can change for various reasons: the evidence does not support the initial claims of the victim or witnesses, people change their versions of what they initially say occurred, the perpetrator claims sex was consensual and so on. Our system of justice relies heavily on tangible evidence, because emotion or perception does not affect it and logical conclusions can be drawn from the science supporting what the evidence represents.

For Full Article:    Investigating rape crimes, Part 2: Evidence collection and analysis


The Evidence Needed Before a “‘True
Bill” May Be Voted
It is the responsibility of the grand jury to
weigh the evidence presented to it. This
is usually done without any explanation
offered by the person being investigated
by the government, in order to determine
whether this evidence persuades that
there is probable cause to believe that
a crime has been committed and that
the person being investigated was the
person who committed it. Remember
that the grand jury is not responsible for
determining whether the person being
investigated is guilty beyond a reasonable
doubt, but only whether there is sufficient
evidence of probable cause to justify
bringing the that person to trial. Only the
evidence presented to the grand jury in
the grand jury room may be considered in
determining whether to vote an indictment.


seizure of property


Author: Angela Grant

Angela Grant is a medical doctor. For 22 years, she practiced emergency medicine and internal medicine. She studied for one year at Harvard T. H Chan School Of Public Health. She writes about culture, race, and health.

69 thoughts on “What is Probable Cause? | Fourth Amendment

  1. Who can cause a probable cause action to be initiated?

    Apparently only law enforcement, not a victim/complainant.

    What is the authority of a citizen’s arrested with respect to probable cause?

          1. Angela, my comment, where I first used the term, was grammatically incorrect. I believe I created confusion. I was trying to clarify.

            Too much energy has been extended due to the inapt, and my inept, use of this platform.

            Probable cause is an interesting legal question. I am glad you discovered it. Please carry on.

            1. I was interested enough to study law, but not enamored enough to practice law… especially criminal law.

              I am in artfully proposing your inquiry into probable cause might also include 1) how the exercise of a ‘citizens arrest’ relates to probable cause 2) whether a citizen can force probable cause to be determined (force an arrest)… or is it solely the discretion of law enforcement.

              If these questions interest you great. If not, proceed as you had envisioned, including ending your inquiry into probable cause.

            2. You can add your thoughts freely to the discussion….I am not a lawyer and welcome all thoughts…as there is something amiss….I thought going back to the law….. If there is something in particular you would like to share please do so….

              I am in no way looking for more research….just sharing of different perspectives….not a quiz.

            3. The videos are rich with information. I noticed an absence of the law…..rights not read…no dialogue or de-escalation no communication or connection to the community ….and almost always the addition of resisting arrest (to charges) when there was no cause for arrest.

            4. The question I posed about a citizen’s initiation of arrest is what came to me by reason of your information about probable cause.

            5. “What is the law for citizen’s arrest?”
              From Wikipedia ‘citizens arrest’…
              United States

              See also: Citizen’s arrest in the United States

              Common law

              Most states have codified the common law rule that a warrantless arrest may be made by a private person for a felony, misdemeanor or “breach of peace”.[50] A breach of peace covers a multitude of violations in which the Supreme Court has even included a misdemeanor seatbelt violation punishable only by a fine. The term historically included theft, “nightwalking”, prostitution and playing card and dice games.[51]

            6. Here your use of probable is unclear to me. Is that some fabricated probable cause for your arrest will result in your resistance that is construed as endangering an officer to the point of fatal self-defense?

      1. “How easily you get flustered?” I experience myself as long suffering, accommodating, non judgmental. YMMV (your mileage may vary).

          1. Long suffering is remaining engaged while there is failure to communicate, for the sake of clarity. Whether I care to influence is wholly a separate matter.

  2. This is a good question and a good article.

    I feel to never to attempt a citizen arrest myself, you could get really hurt or sued even if your right. Gathering evidence by a citizen is another question. Who can cause a probable cause action to be initiated?

    a) This is by citizens gathering information then giving them to your local police departments, again, if attempting this a citizen could get really hurt or sued, always be extremely careful. Police laws are far different than a citizen.

    b) Generally a lawyer is allowed for all cause actions judicial, including probable cause, a citizen would have to prove to the clerk of the courts doing any such actions prior, An upper Chambers Application or above would be needed to surpass. Again, I stress caution for these actions. Laws often are regulated state by state or by country. Canadian province by province or by country. If your not aware of the amendments to the original document your grabbing yourself by the seat of your pants.

    After a 31/2 hour chambers application I was invited to the Judges bench. It started from a simple 20 minute morning appearance. The judge didn’t want to hear it that day and preferred to give 30 days to for me to prepare. But what she didn’t realize that morning before chambers opened by countered the application against me/prove of. I looked out into the empty room and told her this is far to scary and hope to never be there again. She smiled and gave me my rose order.

  3. Great stuff toadink. If you care to consider, what action if any can be brought against a public officer for failure to arrest or failure to charge? Probably none against police/prosecutorial discretion. Consider further then talk about the President not faithfully executing the laws.

    I simply here am contributing questions that come to my mind. I am not compelled to answer them. For me they are merely blossoms now, for others they may be thorns now.

  4. Angela Grant, I believe that probable cause and a warrant issued by a judge should be grounds to legally search an individual’s home. Without either probable cause or a warrant issued by a judge, evidence that is introduced illegally should get the case thrown out of court. Period. Some people can make the argument that if you are not doing anything wrong, you don’t have anything to worry about. True as that may be, the fact is that the 4th Amendment guards the American people against unreasonable searches and seizures.

    1. Thank you for your response. I agree yet I believe the number of unreasonable searches and seizures are up, most directed against those without any safety net, the very poor.

      1. Angela Grant, every U.S. citizen has the right to privacy, to be left alone. I am a leave me alone kind of guy. Now, I think that laws should be abided by. However, in the U.S. we seem to have an avalanche of laws being imposed upon us.

            1. Angela Grant, I was just asking as a curiosity. Nothing more, nothing less. He deals in a wide variety of conspiracy theories. One of them being the assassination of John F. Kennedy. Back to the topic of probable cause, I think that unless police have a warrant to search a premises, any other searches without prior consent of an owner of the residence in question should not be seen as legal, should get any case thrown out of court. Even though engaging in criminal activities are against the law, illegal acquisition of evidence is inappropriate.

            2. Totally agree on the point of warrantless searches. Alex Jones also talks much about conspiracy theories but his pitch is usually out there with racist overtones.

            3. Angela Grant, I don’t mean to be naive, however, is there any verifiable proof that what Alex Jones speaks about has any racist overtones?

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