What do you mean by making it expensive as possible?
A: It's fairly common for large organizations to threaten and sometimes sue for copyright infringement, even where a claim is speculative -- because the litigation costs are extremely high, and no non-lawyer can effectively defend themselves in a copyright infringement action, because of the complexities of the legal claims and procedures involved. Failure to hire a lawyer, typically guarantees a loss, and that means you could be held liable for a great deal of money damages.
Where would I purchase liability insurance?
A: Any large reputable business insurance agency can help you with this.
Could I use news clips and footage from news stations that are covering the case without me being sued by the news stations?
A: For a documentary -- no. You would have to request a license from the various media organizations.
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