You're right, PB. "Immunity to testify" is the way judges and prosecutors combine to get around the Fifth Amendment by using "little fish" to catch "big fish." The logic is, "I want to nail Mr. Big Fish. You're a witness, Little Fish, an accomplice in his crime. If I tell you that you won't be prosecuted for any crimes you admit under oath, you won't be incriminating yourself because there will be no criminal charges as a result. Therefore, the Fifth doesn't apply to you." Yeah, sure. Then, the moment you leave the courtroom, Mr. Big Fish's associates will whack you for being a rat. And if not, everyone on the planet will know you're an admitted criminal. Maybe you won't go to prison. But you'll never hold a job again, etc. The alternative is to go to jail indefinitely for "contempt of court."