When interviewing a subject for a screenplay do you need to take any legal precautions like having the subject sign a waiver before you start that process to protect yourself from any future litigation?
Generally, if you are telling the life story of the person you are interviewing (or his/her story is part of the story you are telling), you need to obtain a release for material he or she shares with you. This is true even if you plan to use only a few of the person’s experiences. Rights to someone’s life story and experiences can be protected by a number of legal principles including right to privacy and right to publicity. These protections are made stronger by the fact that you are actually interviewing the subject.
On the other hand, if you are interviewing the subject about public facts that are not personal, you usually do not need a release. For example, if you interview a physics professor about general time theory to do a story on time travel, you normally do not need a release. However, even in this case, you need to be careful. If the physics professor has some reasonable expectation that she will be compensated for her contribution to your story, she may have some legal rights even if the information itself is public and not legally protected.
To protect yourself when you plan to interview someone for background information, let him or her know you are a screenwriter and looking for general background information. If you do not expect to pay someone for providing information to you, always be clear about that before you get the information. Most people are happy to share information of this nature for free. If you wish for more personal information or experiences or if you plan to use the person as a character in your story, always get a release.