Legal Definitions - mere-evidence rule

The mere-evidence rule was a legal principle in criminal procedure that no longer applies in the United States. Under this former rule, law enforcement officers, even with a valid search warrant, were restricted in what they could seize during an investigation.

Specifically, the mere-evidence rule allowed police to obtain a search warrant to seize:

• Items directly used to commit a crime (known as "instrumentalities of the crime," like a weapon).
• Items obtained as a result of the crime (known as "fruits of the crime," like stolen money).

However, the rule prohibited the seizure of items whose only purpose was to serve as proof or evidence of a crime, without being an instrumentality or fruit themselves. These items, considered "mere evidence," were thought to be protected from seizure, even with a warrant.

This distinction meant that certain crucial pieces of evidence could not be legally taken by police, potentially hindering investigations. However, the U.S. Supreme Court abolished this rule in 1967, recognizing that all evidence relevant to a crime should be subject to seizure with a proper warrant. Today, law enforcement can obtain warrants to search for and seize any item that constitutes evidence of a criminal offense.

Let's look at some examples to understand how the mere-evidence rule operated and why its abolition was significant:

• Example 1: Online Fraud Investigation

  Imagine a suspect is believed to have committed online financial fraud. Under the mere-evidence rule, police with a search warrant could seize the computer used to execute the fraudulent transactions (an instrumentality of the crime) and any funds transferred into the suspect's account from the victims (the fruits of the crime). However, if the police found a handwritten notebook detailing the suspect's elaborate plan for the fraud, including dates, targets, and methods, they could not have legally seized it. This notebook would have been considered "mere evidence" because it wasn't used to commit the crime itself, nor was it gained from the crime; its sole value was to prove the suspect's guilt. Today, with the mere-evidence rule abolished, police would be able to seize the computer, the funds, and the notebook, as all are relevant evidence.

• Example 2: Arson Case

  Consider an investigation into an arson where a building was intentionally set on fire. Under the mere-evidence rule, if police obtained a warrant, they could seize containers of accelerant found at the scene (an instrumentality of the crime). If the suspect had already received an insurance payout for the fire, those funds could also be seized as fruits of the crime. However, if officers discovered a personal diary belonging to the suspect that contained entries describing their motive for setting the fire and their detailed preparations, the diary entries would have been classified as "mere evidence." The old rule would have prevented police from seizing this highly incriminating document. Now, such a diary would be considered crucial evidence and could be seized with a warrant.

• Example 3: Embezzlement Scheme

  Suppose an employee is suspected of embezzling funds from their company. Under the mere-evidence rule, a search warrant might allow police to seize the company's financial records showing the fraudulent transactions (which could be argued as an instrumentality if they were manipulated, or fruits if they represent the stolen funds). However, if during the search, officers found a series of text messages on the suspect's personal phone where they explicitly confessed to a friend about manipulating the accounts and stealing money, these messages would have been considered "mere evidence." Their only purpose was to prove the crime, not to commit it or be gained from it. Therefore, under the old rule, these critical confessions could not have been seized. With the rule abolished, these text messages would now be admissible evidence and could be seized under a valid warrant.