The standard of proof in a civil case such as this is lower than in a criminal court where the prosecution must convince the jury "beyond reasonable doubt". In a civil litigation, the jury needs only to decide the case on "the balance of probabilities" - that it is more probable than not that an allegation is correct.
WHAT WAS DEFAMATORY?
There are two causes of action which Williams identified in his civil suit: Craig's remarks at a press conference about his Dirty Politics booklet and the leaflet itself, which was sent to 1.6 million households.
The jury had to consider each of the actions and whether both, one or neither were defamatory. They concluded both were and then decided how much in damages Williams deserved for "injury to his reputation and the injury to his feelings".
POSSIBLE DEFENCES
QUALIFIED PRIVILEGE:
Before the publication of the Dirty Politics leaflet and the press conference about it, Williams told other members of the Conservative Party and wrote a blog post on Whale Oil about Craig's alleged sexual harassment of his former press secretary, Rachael MacGregor. Craig's lawyer, Stephen Mills, QC, argued this caused a "media firestorm" and was hugely damaging to the politician's character so any response was "entirely proper and justified".
Williams had to disprove this defence and show Craig was acting out of ill-will, with his main motivation being to hurt Williams. Williams' lawyer, Peter McKnight, presented evidence that Craig's response - by holding a press conference, distributing the booklet to 1.6 million households and continuing to repeat the allegations in media interviews - was "out of all proportion" to the first attack. McKnight also argued that Williams' actions in telling members of the Conservative Party about the alleged sexual harassment was justified because those people would want to know about that behaviour.
If Williams proved this, Justice Katz said the onus of proof then "flipped" to Craig to show what he said was the truth or his honest opinion.
TRUTH:
You can't defame someone if what you said about them is true or "materially true" - legal speak for the "gist of it being right", Justice Katz told the jury.
"People are allowed to say true things, even if they're not very nice."
The 11 jurors had to assess the credibility and reliability of each of the witnesses and evidence with Justice Katz instructing them to take particular weight to what Williams and Craig said in court.
Craig had to prove that each of the things he said and published was wholly or mostly true. If they did so successfully, the jury was told to stop there because that was a valid defence to defamation.
However, if they decided the statements were untrue, they had to move to the last defence.
HONEST OPINION:
Craig had to show what he said was presented as his genuine opinion about Williams and wasn't presented as fact.
"It needs to be a recognisable opinion - if it is just a fact his words will not be protected," Justice Katz asked.
IF THE JURY DECIDED NONE OF THE DEFENCES APPLIED
That would mean defamation had occurred and the jury should rule on how much in damages Craig had to pay Williams for ""injury to his reputation and the injury to his feelings". Justice Katz said the $400,000 Williams sought in compensation was a "ceiling" which they didn't need to hit.
They also had to determine if Craig had to pay punitive damages for "flagrant disregard" of Craig's rights". Williams' lawyer Peter McKnight submitted Craig wanted $1.34 million in total.
