A person is 'entrapped' when he is induced or persuaded by law enforcement officers or their agents to commit a crime that he had no previous intent to commit; and the law as a matter of policy forbids conviction in such a case.

However, there is no entrapment where a person is ready and willing to break the law and the Government agents merely provide what appears to be a favorable opportunity for the person to commit the crime. For example, it is not entrapment for a Government agent to pretend to be someone else and to offer, either directly or through an informer or other decoy, to engage in an unlawful transaction with the person. So, a person would not be a victim of entrapment if the person was ready, willing and able to commit the crime charged in the indictment whenever opportunity was afforded, and that Government officers or their agents did no more than offer an opportunity.

On the other hand, if the evidence leaves a reasonable doubt whether the person had any intent to commit the crime except for inducement or persuasion on the part of some Government officer or agent, then the person is not guilty.

In slightly different words: Even though someone may have [sold drugs], as charged by the government, if it was the result of entrapment then he is not guilty. Government agents entrapped him if three things occurred:

- First, the idea for committing the crime came from the government agents and not from the person accused of the crime.

- Second, the government agents then persuaded or talked the person into committing the crime. Simply giving him the opportunity to commit the crime is not the same as persuading him to commit the crime.

- And third, the person was not ready and willing to commit the crime before the government agents spoke with him.

On the issue of entrapment the government must prove beyond a reasonable doubt that the defendant was not entrapped by government agents.

Entrapment charges often stem from vice crimes involving drugs, gambling or prostitution. Law enforcement agencies have the legal right to present their officers as drug dealers, prostitutes, gambling bookmakers or other professional criminals. Contrary to popular belief, these undercover agents do not have to reveal their true identities or legal affiliation when asked. It is not considered police entrapment if an undercover officer presents a supply of drugs to a potential buyer, for example. The buyer of those drugs commits a crime once the deal has been made, not during the initial contact with the undercover officer.

Law enforcement officers must be aware of their limitations during a sting operation to avoid later accusations of entrapment. An undercover officer working as a prostitute, for example, cannot initiate a conversation leading to the customer's solicitation offer. A defendant arrested for solicitation of a prostitute could claim that the undercover officer was flirtatious or made physical contact before identifying herself as a prostitute. An argument could be made that the solicitation was based on the officer's behavior, not on the defendant's intention to commit a crime.

Claims of entrapment can be notoriously difficult to prove. Some successful claims against law enforcement agencies have centered around the idea of a 'virtue test'. Police cannot select random citizens to participate in organized sting operations in hopes of generating an arrest. There must be some compelling evidence that a specific individual has a propensity for committing such a crime.

Another reason entrapment is difficult to prove in court is the criminal history of the defendant. If the prosecution can demonstrate a previous history of similar crimes, then it becomes extremely difficult to prove entrapment. Providing an opportunity to commit a crime is not considered entrapment.

This is why police stings involving Internet sex crimes have been successful. Defendants may claim that adult police officers posing as underage chatroom participants constitutes entrapment, for instance. The reality is that the undercover agent only provided an opportunity for the suspect to initiate illegal conversations.