Legal Definitions - Blockburger test

The Blockburger test is a legal standard used in criminal law to determine whether a person can be prosecuted or punished for two different crimes that arise from the same incident without violating the constitutional protection against double jeopardy.

Double jeopardy prevents someone from being tried or punished twice for the same offense after a conviction or acquittal. The Blockburger test helps courts decide if two charges are actually the "same offense" for double jeopardy purposes.

Here's how it works: A court compares the legal elements of each crime. If each crime requires proof of at least one element that the other crime does not, then they are considered separate offenses. In such cases, a person can be charged with, convicted of, and punished for both crimes. If one crime does not contain any element that the other crime lacks (meaning one crime is entirely encompassed within the other), then they are considered the "same offense," and separate punishment for both would typically be prohibited.

Crucially, the Blockburger test focuses on the specific legal elements that define each crime, not on the particular facts or evidence presented in a given case.

• Example 1: Separate Offenses

  Imagine a scenario where a person breaks into a house (burglary) and, once inside, physically assaults the homeowner (assault and battery). If charged with both crimes, a court would apply the Blockburger test.

  • Burglary typically requires unlawful entry into a building with the intent to commit a crime inside.
  • Assault and Battery requires an intentional act that causes harmful or offensive contact with another person.

  The Blockburger test would likely find these to be separate offenses because burglary requires unlawful entry (which assault and battery does not), and assault and battery requires physical contact (which burglary does not). Even though both acts occurred during the same incident, they each have distinct legal elements. Therefore, the individual could be punished for both.

• Example 2: Same Offense (Lesser Included)

  Consider a situation where someone is charged with felony murder, which is a type of murder that occurs during the commission of a dangerous felony (like robbery or arson). If the prosecution also tried to charge them separately with the underlying felony itself (e.g., robbery) for the same incident, the Blockburger test would be applied.

  • Felony Murder requires the commission of a felony (like robbery) and a death occurring during that felony.
  • Robbery requires taking property from a person by force or threat.

  In many jurisdictions, robbery would be considered a "lesser included offense" of felony murder when the robbery is the predicate felony for the murder charge. The elements of robbery are entirely contained within the elements of felony murder in this context. Robbery does not have any element that felony murder lacks. Therefore, under the Blockburger test, punishing the individual for both felony murder and the underlying robbery for the same act would likely violate double jeopardy protections, as they would be considered the "same offense."

• Example 3: Distinct Elements Despite Shared Facts

  Suppose an individual is pulled over by police and found to be driving under the influence of alcohol (DUI) and also possessing an unregistered firearm (unlawful possession of a firearm) in the vehicle. Both offenses occurred at the same time and place.

  • DUI requires operating a vehicle while impaired by alcohol or drugs.
  • Unlawful Possession of a Firearm requires possessing a firearm without proper registration or permit.

  The Blockburger test would determine these are separate offenses. DUI requires operating a vehicle while impaired, which is not an element of unlawful firearm possession. Conversely, unlawful possession of a firearm requires possessing an unregistered weapon, which is not an element of DUI. Even though the discovery of both crimes happened during a single traffic stop, their legal definitions involve entirely different sets of elements, allowing for separate charges and punishments.