Criminal Attempt: The Substantial Step Test

In criminal law, the line between mere preparation and a punishable attempt is both critically important and notoriously blurry. Understanding where this line is drawn determines when society intervenes to prevent harm and holds individuals accountable for their intentions. The Model Penal Code (MPC) revolutionized this area by introducing the substantial step test, a modern standard that broadens liability to capture dangerous conduct before the final act, shifting focus from how close someone was to completing the crime to how clearly their actions reveal a criminal purpose.

The Purpose and Punishment of Criminal Attempt

Criminal attempt is an inchoate offense, meaning it is a crime that is begun but not completed. You are liable for attempt when, with the intent to commit a specific crime, you take some action toward its commission but fail to consummate it. The law punishes attempts for two primary reasons: to deter dangerous behavior before harm occurs and to sanction individuals who have demonstrated a firm criminal purpose. However, punishing thought alone is antithetical to a free society; the law requires an "act" to manifest this intent. The central challenge, therefore, is defining the precise point at which innocent preparation crosses into culpable attempt. Different legal systems have developed various tests to solve this puzzle, with the MPC's substantial step test representing a significant departure from earlier, more restrictive common law approaches.

Common Law Tests for Attempt

Before the MPC, courts used several tests to distinguish preparation from attempt, each with varying thresholds for liability. These common law tests often required the defendant to be very close to completing the crime.

The dangerous proximity test asks whether the defendant's actions came dangerously close to achieving the criminal result. Factors include physical nearness to the victim, the seriousness of the contemplated crime, and the likelihood of success. For example, purchasing a gun is preparation, but pointing it at a victim and pulling the trigger (which fails due to a misfire) is attempt under this test, as the act is dangerously proximate to murder.

The last act test is the most restrictive standard. Liability for attempt attaches only after the defendant has performed every act they believed necessary to complete the crime. Using the same example, liability would not arise until the trigger was pulled, even if the defendant had the victim at gunpoint for hours. This test is rarely used today because it allows dangerous individuals to escape liability until the very last moment, undermining the preventive goal of attempt law.

The equivocality test (or res ipsa loquitur test) examines whether the defendant's actions, by themselves, unequivocally demonstrate a criminal intent. If the conduct is ambiguous and could be interpreted as innocent, it is merely preparation. For instance, buying a ski mask and a crowbar could be for legitimate reasons, but using them to pry open a bank window at night unequivocally signals burglary. This test is criticized for being unrealistically demanding, as few acts are completely unambiguous without evidence of intent.

The Model Penal Code's Substantial Step Test

Dissatisfied with the limitations of common law tests, the drafters of the Model Penal Code formulated a more expansive and pragmatic standard in Section 5.01. A person is guilty of an attempt if, acting with the culpability required for the completed crime, they engage in conduct that constitutes a substantial step toward the commission of the offense. Crucially, the substantial step must be strongly corroborative of the actor's criminal purpose.

This test intentionally broadens attempt liability beyond the common law's focus on proximity. The MPC shifts the inquiry from "how close was the defendant?" to "how clear was their intent based on what they did?" A substantial step is any action that is a significant start toward the crime and provides clear evidence of a firm intent to carry it through. The MPC provides illustrative examples, such as lying in wait, enticing the victim to the planned crime scene, reconnoitering the place, unlawfully entering a structure, or possessing specialized tools for the crime under circumstances showing they were to be used for unlawful purposes.

Comparing the Substantial Step with Common Law Tests

The substantial step test is designed to address the shortcomings of the common law approaches. Unlike the dangerous proximity test, it does not require the defendant to be on the brink of success. Conduct that is further removed in time and space can still be a substantial step if it strongly corroborates intent. For example, under the MPC, renting a car and driving to a bank with a note demanding money might constitute a substantial step toward robbery, whereas under the proximity test, this might still be considered preparation.

In contrast to the last act test, the substantial step test allows for much earlier intervention. The defendant need not have performed the final act. Purchasing materials to build a bomb with a proven plan to use it could be a substantial step, whereas under the last act test, liability would only attach upon placing or activating the device.

The substantial step test also modifies the equivocality test. While both look for evidence of criminal purpose, the MPC explicitly allows the consideration of all attendant circumstances, including the actor's statements and prior actions, to determine if the step corroborates intent. The conduct itself does not have to speak unequivocally; it can be interpreted in light of contextual evidence. This makes the MPC standard more workable for prosecutors and better aligned with how intent is proven in other areas of criminal law.

Application in Modern Jurisprudence

Most states have adopted some form of the substantial step test, either directly from the MPC or through similar judicial standards. Applying it requires a careful, case-by-case analysis. Consider a classic law school hypothetical: Dan intends to kill Victor. He researches poison online, purchases it from a store, and drives to Victor's house. Under the last act test, attempt liability begins only when Dan administers the poison. Under the dangerous proximity test, it might begin when he is at Victor's door. Under the substantial step test, however, the purchase of the poison with a documented plan could itself be a substantial step, as it strongly corroborates his homicidal intent, especially if paired with other evidence like threatening messages.

Courts often look for actions that are not readily abandonable without concrete steps backward. Merely planning a crime or acquiring generic tools is usually insufficient. But once you take a step that concretely sets the plan in motion and demonstrates a commitment to execute it, you have likely crossed the line into attempt under the MPC. This framework empowers law enforcement to prevent crimes more effectively while requiring robust evidence of criminal purpose to protect against punishing innocent preparation.

Common Pitfalls

When analyzing attempt problems, students often make predictable errors. First, confusing preparation with attempt based on intent alone. Remember, a guilty mind (mens rea) is necessary but not sufficient; you must always identify a substantial step or its equivalent under other tests. Strong intent does not transform early planning into an attempt.

Second, applying the tests in isolation without considering jurisdictional rules. In an exam, you must identify which test the jurisdiction uses. A common mistake is to discuss the substantial step test when the problem is set in a jurisdiction that follows the dangerous proximity rule. Always anchor your analysis in the specified law.

Third, failing to fully argue corroboration under the substantial step test. Do not just state that an act was "substantial." You must explain how it strongly corroborates criminal purpose by linking the action to the specific intent, perhaps by showing it served no lawful purpose or was a pivotal move in the planned sequence.

Finally, overlooking abandonment or renunciation as a defense. Under the MPC, even after a substantial step is taken, a defendant may have a defense if they voluntarily and completely renounce their criminal purpose. A common error is to assume attempt liability is fixed once a step is taken, without considering whether the defendant later changed their mind in a manner that negates culpability.

Summary

• The Model Penal Code's substantial step test broadens attempt liability by focusing on conduct strongly corroborative of criminal purpose, rather than physical proximity to the completed crime.
• It contrasts with stricter common law tests: the dangerous proximity test (requiring nearness to success), the last act test (requiring the final act), and the equivocality test (requiring unambiguous conduct).
• A substantial step is a significant action that marks the beginning of execution and provides clear evidence of intent, such as reconnoitering a target or possessing specialized tools for the crime.
• In application, this test allows for earlier law enforcement intervention while requiring robust contextual evidence to distinguish culpable attempt from innocent preparation.
• Always determine which attempt test governs in a given jurisdiction and analyze each element—intent plus the requisite act—systematically to avoid common analytical pitfalls.