What Impossibility Means

What Impossibility Means

Attempt, conspiracy, and solicitation are called inchoate offenses because each punishes conduct aimed at a crime that has not been completed.¹ In most attempt cases the crime stays unfinished because something interrupts the plan: the police arrive, the victim escapes, or the defendant loses nerve and stops. Those cases ask how far the defendant had progressed toward the crime before the interruption.² A person can also attempt a crime and fail with no interruption at all, because the outcome differs from the one the person anticipated.³ Criminal law calls those cases impossibility, and they raise a different question from the interrupted ones.

An impossibility claim can be stated in the defendant's own terms: had things been as I believed, my conduct would have been a crime, but they were not. The formal version says that an undertaking fails because of impossibility when the actor would be committing a crime if he did everything he intends under the conditions he believes exist, yet what he actually does is not the intended offense because those conditions are not what he believes them to be.⁴ The failure therefore sits in the gap between the defendant's picture of the world and the world itself. The defendant carries out the plan, and the completed crime is unavailable only because a fact or a legal premise the defendant relied on was wrong.

Courts illustrate the idea with a handful of recurring scenes. In People v. Thousand the court listed four: a pickpocket who reaches into an empty pocket, a man who attempts nonconsensual intercourse but is impotent, a buyer who receives property that was not in fact stolen, and a hunter who shoots at a stuffed decoy deer and is charged with attempting to hunt deer out of season.⁵ The unloaded gun pointed at a victim is a fifth scene of the same kind.⁶ In every one of them the defendant's criminal intent is plain, yet proof of at least one element of the completed offense cannot be drawn from what the defendant actually did. That is why the completed crime cannot be charged and why the live question becomes whether the defendant may be convicted of the attempt, which depends on whether impossibility is a defense.⁷

Only the second scene presents an impossibility claim, because only there does the failure trace to something the defendant had wrong. A student who treats every failed attempt as an impossibility problem will apply a doctrine that has nothing to say about the tackled gunman, since an interrupted plan is not an impossibility case. The tackled gunman's liability turns on how close the conduct came to completion, and no mistaken belief enters the analysis.

The traditional response sorted impossibility claims into two groups. Under the traditional approach, legal impossibility is a defense to attempt and factual impossibility is not.⁸ Factual impossibility describes a defendant who cannot accomplish what he intends because of a physical fact unknown to him, and the empty pocket is the standard example.⁹ Legal impossibility, in its core sense, describes a defendant whose intended conduct is not a crime at all, even though he believed it was.¹⁰ A driver who turns right on a red light, imagining the turn to be a crime in a jurisdiction that permits it, has done what the driver meant to do, yet there is no offense for the conduct to be an attempt at.¹¹ The two groups are treated differently because of what each defendant shows. The pickpocket has shown a willingness to commit larceny, a crime that exists, while the driver has shown a willingness to break a law that was never written, and so cannot have the mental state needed to attempt any particular offense.¹²

The two-way split is tidier on paper than in practice. Scholars identify four types of impossibility: factual, inherent, pure legal, and hybrid legal.¹³ Inherent impossibility covers means so unlikely to work that prosecution seems a waste of effort, and hybrid legal impossibility covers certain mistakes about legal status, and each receives its own section below.¹⁴ Courts have struggled to apply even the two basic labels, and decisions on similar facts have come out differently. Property that was once stolen but had been recovered before the defendant bought it, believing it still stolen, is the well-known case in which courts reached a result critics say used the wrong label.¹⁵ That kind of confusion is one reason the Model Penal Code abandoned the defense of impossibility, apart from the case in which the conduct is not a crime at all.¹⁶

Because the labels are unreliable, the analysis starts from a question that does not depend on them: if the facts were as the defendant believed, would the defendant have committed the crime?¹⁷ A yes points toward liability for the attempt. The question looks to belief because attempt law measures what the defendant intended and did, and a mistake about the world changes neither. The Model Penal Code's commentary makes the same point about luck: when a defendant fails to complete the offense because of a fortuity, such as a bullet that misses, excusing the defendant would treat identical culpability unequally.¹⁸ A wrong fact about the world plays the same role as the missed bullet. This first version of the question is a working approximation, and the sections that follow sharpen it by separating mistakes about facts from mistakes about law and by handling the hybrid cases.