Police perjury

Police perjury (or testilying in United States police slang) is the act of a police officer giving false testimony. It is typically used in a criminal trial to "make the case" against a defendant who the police believe to be guilty when irregularities during the suspect's arrest or search threaten to result in acquittal. It has broader meanings. It also can be extended further to encompass substantive misstatements of fact for the purpose of convicting those whom the police believe to be guilty, or even to include statements to frame an innocent citizen. More generically, it has been said to be: "Lying under oath, especially by a police officer, to help get a conviction."

Testilying is a portmanteau of testify and lying. Defendants who embellish their own testimony, particularly when no evidence contradicts them, can also be said to be testilying. It is said to be a type of police corruption.

The word testilying and its meaning have been publicized by defense attorney Alan Dershowitz, notably in a 1994 New York Times article, "Accomplices to Perjury," in which he said:

As I read about the disbelief expressed by some prosecutors... I thought of Claude Rains's classic response, in Casablanca on being told there was gambling in Rick's place: "I'm shocked—shocked." For anyone who has practiced criminal law in the state or Federal courts, the disclosures about rampant police perjury cannot possibly come as a surprise. "Testilying"—as the police call it—has long been an open secret among prosecutors, defense lawyers, and judges.

There seems to be little doubt that the practice occurs, is not limited to any region of the country, and that "testilying" is a common name for it. A 2003 Boston Globe editorial noted:

In the early 1990s, the Mollen Commission peeled away layers of falsehood in the New York City Police Department, including false statements on warrant applications, creation of confidential informants out of whole cloth, and lies told to establish probable cause for stopping and searching vehicles. So-called "testilying," however, is not limited to any one area or police department. The problem has become so acute that juries nationwide routinely express skepticism about law enforcement testimony, such as drugs found "in plain view".

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