Be aware: If one officer knows it, they all do

The 2014 Colorado decision of Grassi v. People addresses whether knowledge of one officer can be treated as known to another. This is not a question of gossip; instead, it can have serious implications for an accused's Fourth Amendment rights.

In Grassi, a man was involved in a single-vehicle car accident in which he was severely injured and his passenger was killed. The police investigation led state police to conclude that alcohol may have been involved, as there was no evidence of any external factors (such as mechanical problems or another vehicle) leading to the crash, nor were there any signs the driver had attempted to swerve or brake.

After the investigation of the crash site, and while the driver was still unconscious in the hospital, a supervising officer directed a third trooper who had not been present at the accident to go to the hospital and investigate whether alcohol was involved and order a blood test if he believed it was. The trooper learned that the defendant was the driver in the accident and smelled alcohol on him. The trooper then ordered a blood alcohol test which showed that the driver's blood alcohol content exceeded the legal limit. State law allows the drawing of an unconscious driver's blood if there is probable cause to believe that the person was driving under the influence.

The defendant argued that the specific trooper who was at the hospital did not have probable cause to order the test. Specifically, he based his argument on the fact that the trooper in the hospital had not been assigned to the case as of when the investigation of the accident scene was completed, so was not involved when probable cause was found.

Courts in the United States recognize a rule known as the Fellow Officer Rule. In the words of the U.S. Supreme Court, from the case Illinois v. Andreas, this means that "the knowledge of one [officer] is presumed shared by all." This can include among officers not present at the scene, so, for example, an officer who is told of evidence against a suspect by another officer has just as much probable cause to make an arrest as the first officer. However, this knowledge must be had prior to the search or arrest. In other words, the police may not make an illegal arrest and then search through their records in order to justify the arrest after the fact.

The question the Colorado Supreme Court was called to address was one of timing. Since the trooper who ordered the blood alcohol test was not assigned to the case until several hours after the accident, and after the other troopers' investigation of the scene was completed, the defendant argued that the Fellow Officer Rule did not apply.

The Colorado Supreme Court disagreed. It ruled, instead, that the Fellow Officer Rule serves to pool the investigating officers' knowledge, rather than requiring direct, linear communication from one officer to another. This means that even though the officer at the hospital was unaware of the specific results of the investigation at the crash site, he was considered to have all knowledge that the police as a whole had at the time that he ordered drawing the driver's blood. The court concluded that the police as a whole had sufficient knowledge to make the blood test reasonable.

In any case involving police action, the facts of each case are important. The legal principles at issue can also be complex. Therefore, it is important to call an experienced attorney if you face any police action, to ensure that your rights are protected.