The most important thing to know is how to use the footage that you have found. Your rights, as well as the access to footage, depends on exactly what you are looking for. Since clandestine footage is usually defined as footage that may have been obtained illegally and usually does not have an author attached to it, its use is almost never a copyright violation. Unless you are going directly to the source or have an intermediary organization that is willing to give you the raw footage you might have to resort to using compilations of footage that you find online. For example, Animal Liberation Front videos are often recorded by people who take direct action against animal exploitive industries. In such cases cells may videotape themselves releasing animals from a commercial fur farm, destroying a live vivisection laboratory, or setting fire to the headquarters of a logging operation. In these cases the tapes are then sent anonymously to press organizations, such as the Animal Liberation Front Press Office, who then use them in press releases that go out to media internationally. It is often difficult to get this footage, but there are hundred of compilation videos that you can find online with a little effort. Usually these are edited to music, and include other material such as news real footage and interviews. To use this footage you simply have to identify what videos are strictly the ALF footage and then separate that. Make sure that each video clip you show is in its entirety and does not have any cuts or alterations made to it by the previous editor because that will make it an original creative work. Once you have these little unaltered pieces you can then edit them together at your own discretion. The producers of these videos may have rights over them, but they cannot over the raw footage. As long as you are using clips that have not had any independent artistry done to them outside their original context then you are free to use them.