There is sometimes legal justification for using someone else's copyrighted or other protected material without permission. Nevertheless, there is always some level of risk when you use someone else's material without permission. While the risk may be minimal, it is never zero. Your claim that your use is protected by copyright fair use or by the First Amendment is not a guarantee that your unauthorized use will not trigger legal action from the rights owner.
That's why the decision of whether to use a particular copyrighted work without permission often revolves around a risk assessment. You must decide whether or not you can and want to accept the risk. Here are some of the questions I ask when conducting such a risk assessment:
Would your use upset the typical rights owner? This is a reality check. Put yourself into the shoes of the rights owner. Would you be angry and want to take legal action if someone used your material without your permission in the way you want to use the rights owner's material?
Has the rights owner previously objected to similar uses of material? It is a good bet that rights owners who have been aggressive in protecting their rights in the past will continue to be aggressive in protecting their rights in the future.
Does the rights owner have the resources and knowledge to pursue an action against you - even if the action would be without merit? A well-established company with an in-house legal department can more easily make a fuss about your production than can an individual with more limited resources. Nevertheless, do not completely dismiss the cash-strapped smaller rights owner. If his claim is legitimate and offers the possibility of having the losing side pay attorneys' fees, he can probably find an attorney to assist him on a contingency basis.
How much exposure will your production receive? The more exposure your production receives, the more likely it is that your unauthorized use will come to the attention of and spark an objection from the rights owner.
Will your unauthorized use expose other people to risk? Rights owners filing lawsuits typically sue everyone in the distribution and creation chain. Likely targets include authors, publishers, producers, record labels, advertising companies, broadcasters, and distributors. Dragging your partners into a lawsuit is not good for business.
Is there anyone involved in your production who has ample resources? People or organizations who have or who are perceived to have a significant amount of money make attractive targets for lawsuits.
Will you ever need anything from this rights owner? Relationships are important in the media industry. Will you need to return to the same rights owner to request rights for a future production? If yes, using the rights owner's work without authorization - even if he takes no formal action against you can sour your future negotiations for rights you may need from that owner at a later date.