Undercover law enforcement officers from local and federal Northeast Georgia agencies recently have netted arrests by posing as poachers, drug dealers, militia members and 15-year-old girls. Such investigative tactics often rankle the targets, who claim a pure mind was pushed to criminality by an officer, alluding to the legal concept of “entrapment.” But that’s a legal defense far more difficult to prove than perhaps it’s often construed, legal experts said.