means that you cannot say or publish something that hurts the reputation of a person or organisation. In some countries the truth of the statement is a defense, in others defendants also have to prove that the statement was in the public interest. No financial damage has to be proven.
covers any agreement between two or more people to harm a third party using illegal methods such as trespass or defamation. It means that any individual or group that is part of a coalition campaigning on an issue can be held liable for the illegal actions of others in the coalition.