Q From George Mannes: Can you shed any light on the evolution of the word cop-out? Webster appears to define it as a confession of a crime to the police, but in my lifetime, every time I’ve heard it used it doesn’t have that criminal connotation. I’ve always understood it to mean an evasive action or comment that avoids making a difficult decision.
A The Webster definition you mention refers to a much older form of the verb to cop out, which has had a variety of senses in American slang. Your form has evolved from it.
It’s first recorded about the end of the nineteenth and beginning of the twentieth centuries, meaning to take something for oneself (“He simply can’t lose, can’t fail to cop out the best-looking girl with the biggest bank-roll in town”. That’s from The Fortune Hunter, by Louis Joseph Vance, published in 1910). This was based on one of the many standard English senses of cop — to snatch, steal or grab. Around the 1930s, cop out began to take on another of the senses of cop — to catch or apprehend (which is what a cop in the sense of a policeman does, a slang term which came from the same source but rather earlier). To cop out here meant to plead guilty, especially to a lesser charge as the result of plea bargaining.
The big change came in the 1950s. To cop out evolved to refer to making a full confession of some crime or misdemeanour, usually but not necessarily to the police. From this it moved to mean backing down or surrendering, or giving up your criminal or unconventional lifestyle; in the 1960s it developed still further to mean that a person was evading an issue by making excuses or taking the easy way out.
In parallel with this, your noun form, a cop-out, developed from the late 1950s onwards until it, too, became nationally known in the mid-1960s (and quickly spread to Britain and other countries, too) to mean an excuse, a pretext, a going back on your responsibilities to avoid trouble, a cowardly or feeble evasion.