

Police are limited in how they obtain evidence. If I’m squatting on your farm and I see you bury a body you better believe that my testimony can be used as evidence lmao.
The activists will be prosecuted separately if their identities are discovered, and their lives will be destroyed in the interest of protecting the meat industry and preventing people who eat meat learning the necessary abuses.
Illegally obtained evidence can be admitted to court if it is decided that it’s more important that it be admitted than not. For example if I illegally record you admitting to being a serial killer to me, this is likely to be admitted since murdering lots of people is a much more serious crime than illegal recording. See 138 Discretion to exclude improperly or illegally obtained evidence in https://www.legislation.gov.au/C2004A04858/latest/text