What are the consequences of granting immunity to a witness in the People v. Badgett case?

"We make these representations knowing she has already provided information to us by way of statements which makes her a material witness on the question of guilt in the People v. Badgett case. It should also be made clear that if we verify her statements and/or any other evidence presented to us, that we would intend to petition the court for a full grant of immunity pursuant to section 1324 of the Penal Code at the time of trial, or sooner if her testimony is needed for the purposes of a preliminary hearing or indictment." (Italics added.)