A few states have enacted vicarious liability statutes seeking to hold one person responsible for the acts 
of another, even when they did not provide any assistance and may have not even known about the other’s 
behavior. These statutes, generally violate our belief in individual responsibility that only people who do 
something wrong should be blamed for the crime. Vicarious liability imputes (transfers) both the criminal 
intent and the criminal act of one person to another. Courts generally invalidate these purported vicarious 
liability statutes but have at times upheld liability based upon an employer/employee relationship or a parent/
child relationship. 
Defenses 
Assuming the government has proven all the elements of a crime, defendants may nevertheless raise 
defenses that may result in their acquittal. Defense is a general term that includes perfect and imperfect 
defenses, justifications and excuses, and procedural defenses. 
Perfect and Imperfect Defenses 
A perfect defense is one that completely exonerates the defendant. If the defendant is successful in raising 
this defense, meaning the jury believes him or her, the jury should find the defendant not guilty. An 
imperfect defense is one that reduces the defendant’s liability to that of a lesser crime. If the jury believes 
the defendant, it should find the defendant guilty of a lesser charge. 
Negative Defenses and Affirmative Defenses 
Sometimes the government is unable to prove all the elements of the crime charged. When this happens, 
the defendant may raise a negative defense claim. The defendant doesn’t have to prove anything, instead, 
he or she just argues that something is missing in the state’s case, that the state did not prove everything the 
statute said it had to prove, and therefore the jury should find him or her not guilty. For example, when 
charging a defendant with theft, the state must prove that the defendant intentionally took the property of 
another. If the jury finds that the defendant did not intend to take the property, or took property that that 
was rightfully his or hers, then it should find the defendant not guilty. Negative defenses at their essence 
are claims that there are “proof problems” with the state’s case. The defendant’s claim that the state failed to 
prove its case does not depend on whether the defendant has put on any evidence or not. 
An affirmative defense requires the defendant to put on evidence that will persuade the jury that he or she 
should either be completely exonerated (for a perfect defense) or be convicted only of a lesser crime (for an 
imperfect defense). The defendant can meet this requirement by calling witnesses to testify or by introducing 
physical evidence. Because of the presumption of innocence, the burden of proof  (the requirement that the 
party put on evidence and persuade the fact-finder) cannot switch completely to the defendant. The state 
must ultimately bear the burden of proving defendant’s guilt by putting on enough evidence that defendant 
has committed the crime by proving each and every material element of the crime, and it must convince 
the jury of this guilt beyond a reasonable doubt. However, when the defendant raises an affirmative defense, 
the burden of production or persuasion switches, at least in part and temporarily, to the defendant. The 
defendant’s burden is limited, however, to prove the elements of the defense he or she asserts. 
Note the interplay of negative defenses and affirmative defenses. Even if a defendant is unsuccessful in 
raising an affirmative defense, the jury could nevertheless find him or her not guilty based upon the state’s 
failure to prove some other material element of the crime. 
Justifications 
Sometimes doing the right thing results in harm. Society recognizes the utility of doing some acts 
in certain circumstances that unfortunately result in harm. In those situations, the defendant can raise a 
justification defense.  Justification defenses allow criminal acts to go unpunished because they preserve an 
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