How Immunity Works In Federal Criminal Cases
If you're involved in a federal investigation and you have information that the government wants or the government would find useful, one thing that may happen is there’ll being immunity negotiations. You may be able to get some kind of immunity for sharing the information you've got.
There are really three kinds of immunity that are most often talked about in that kind of situation, so let me talk about them.
First there is proffer letter immunity. Normally the government won't give you any more significant kind of immunity without knowing a lot about what you’re going to say. So what they do is they give you what’s called is a king for a day letter or a queen for a day letter. It’s the weakest kind of immunity. What it does, is it allows you to go in and you can talk to the government and what you say won't be used against you later in a criminal proceeding, with two exceptions.
First, they can use what you say to collect evidence to use against you. For example, if you tell them the you committed a murder they can't use the fact that you told them you committed a murder against you, but if they go dig up a body right were you told him it was and they find your driver's license on the body, they can use the fact that they found your driver's license on the body against you. They can use the information to collect other evidence, in other words.
The second exception is if you ever say something different in court, they can use the fact that you said something else earlier against you that later proceeding. Again, it's a relatively week kind of immunity and it doesn't guarantee that nothing bad will happen to you for talking to them. But it gives you a little bit protections so you can you sort of start a conversation with the government.
The second kind of immunity that people often get is letter immunity. This is basically an agreement by the government, negotiated between the government and your lawyer. And what that kind of immunity gives you is a promise by the government that they won't use what you say against you, either to find other evidence or for any kind of prosecution. It's a relatively strong kind of immunity and what it winds up meaning, more often than not, is that if you've got that kind of immunity you're not going to get prosecuted later. Because if you get prosecuted later the government will have to go to a hearing, an ethics hearing. They'll have to prove that any evidence they found that they want to use against you didn't come from what you told them earlier.
The third kind of immunity is called statutory immunity. If you get statutory immunity it means that a federal district court judge looked at the possible testimony you would give it a grand jury proceedings or in a trial and decided that you have a legitimate Fifth Amendment right. You had a right not to say anything at all and that judge, she is ordering you to talk at that proceeding. And in exchange for that, because you still have a Fifth Amendment right, what you say can't be used against you, either directly in terms of having those words used against you, or indirectly in terms of the government finding other evidence to use against you.