Yes of course. It is actually one of the oldest and most widely used defenses in law. It does not always work, maybe it fails a lot more than it succeeds. But when it succeeds, it succeeds very well.
Of course, it is not actually called or thought of as the Chewbacca Defense. That nomenclature comes from an episode of South Park that parodied courtroom trials conducted by the late legendary defense attorney Johnnie Cochran. But the concept used in that episode is very real and very prevalent in American courtrooms.
The Chewbacca Defense relies on several truisms about trials; (1) juries are often intimidated, confused or bewildered about anything that goes on in a courtroom; (2) most people think they know way more about the law and legal concepts then they really do; and (3) anything can sound convincing if said in an authoritative , confident and persuasive manner.
Basically the Chewbacca defense posits that when you have a case where the law and/or the facts seem to be going against you, the best thing to do is try to confuse the jury to the point where they feel that everything about the proceeding is so absurd and incomprehensible and that by accepting and ratifying their confusion , you have gained their acceptance and trust. This plays on the factors noted above, mainly that legal proceedings often are absurd to most people and that the white elephant in the room is that nobody really understands what the heck happened or is going on. By acknowledging the white elephant in the room or if you prefer, that the emperor has no clothes, you gain the jury’s sympathy and trust. They want to believe you, because unlike everybody else, you are talking sense.
In the South Park episode, the fictional Johnnie Cochran was defending a record company against a claim of copyright infringement brought by one of the characters and also suing that character for harassment. The case appears to be a slam dunk verdict against the record company as there is a tape recording which proves that the copyright was in fact infringed. At closing arguments, Cochran delivers the following summation.
Ladies and gentlemen of this supposed jury, I have one final thing I want you to consider. Ladies and gentlemen, this is. Chewbacca is a from the planet . But Chewbacca lives on the planet . Now think about it; that does not make sense! Why would a Wookiee, an 8-foot-tall Wookiee, want to live on Endor, with a bunch of 2-foot-tall ? That does not make sense! But more important, you have to ask yourself: What does this have to do with this case? Nothing. Ladies and gentlemen, it has nothing to do with this case! It does not make sense! Look at me. I’m a lawyer defending a major record company, and I’m talkin’ about Chewbacca! Does that make sense? Ladies and gentlemen, I am not making any sense! None of this makes sense! And so you have to remember, when you’re in that jury room deliberatin’ and the Emancipation Proclamation, does it make sense? No! Ladies and gentlemen of this supposed jury, it does not make sense! If Chewbacca lives on Endor, you must acquit! The defense rests.
By acknowledging the absurdity of even his own argument and its connection to these equally absurd legal proceedings , Cochran wins the jury over and gets a verdict for his client. In real life this can happen also. In fact many people say the real Cochran used it in his defense of OJ Simpson at Simpson’s criminal trial. Cochran goaded the prosecutor into trying to force Simpson into putting on the leather glove that was found at the scene. Doing so at trial made no sense. The glove has been soaked in blood and other liquids and frozen and since Simpson wore other gloves underneath, it proved nothing. But by making a big presentation of it and by convincing the prosecutor to buy in, Cochran successfully used the Chewbacca defense. Since Chewbacca lived on Endor, you must acquit.
The Chewbacca defense is most useful in cases, similar to OJ Simpson, where scientific and/or forensic evidence is so overwhelmingly against one side that he or she or it has no choice but to try to dazzle the jury into thinking that the issues regarding this evidence are so complex and beyond their ken that they cannot fairly resolve them in in this proceeding and must therefore disregard the evidence as untrustworthy or insufficient. As one expert put it:
It’s a trial nightmare with DNA evidence. Most everyone remembers the O.J. Simpson trial where DNA testimony was the longest part of it. It’s often said that juries rebel against complicated scientific evidence. DNA evidence has the potential to be exculpatory, but DNA reports, with all their certitude in terms of probability, are used less for exoneration and more for confusion. The reports sometimes express probabilities out to so many decimal places that they cover the potential population of three or four solar systems.
What can you do if you’re a defense lawyer and the report says “inclusion”? Well, before you try any last-minute strategies of claiming your client left their DNA at the scene by accident or during a previous visit (as you might with fingerprints), you’ll probably want to obtain your own test, but this has the same self-incrimination effect as if you put your client on the stand, and in any event, further DNA testing will only cause delay and additional expense. About the only thing you can do is attack the lab for its (lack of) quality assurance and proficiency testing, or use a “Chewbacca defense” (thanks to the South Park TV show for this phrase) and try to razzle-dazzle the jury about how complex and complicated the other side’s evidence or probability estimates are.
Digital evidence also has similar problems and a skillful advocate can use all kinds of red herrings and logical fallacies to distract a jury away from the real meaning and probabilities the evidence suggests. There are journal articles in several publications which discuss the Chewbacca defense and its application to digital evidence.
Lest I sound too cynical, let me hasten to add that the Chewbacca defense does not always work and many juries see through such tactics and punish the attorney using them. Skillful and experienced attorneys and experts know how to present complicated and tricky scientific evidence to a jury in an manner that they can understand and relate to. And judges know how to instruct the jury on how the law should be applied to the evidence and to the case. But the question asks if the defense has ever been successfully used in court and the answer is clearly Yes.