Get the best expert you can. He ( or she obviously ) must be highly expert in relation to the issues upon which he has been asked to give an opinion. He must fully and properly understand the role of an independent expert, study the rules about giving expert evidence and be both willing and able to comply with them.
Then it is necessary to consider whether the expert has experience of giving evidence in court or if not whether he looks likely to be somebody who will be able to deal with the court hearing process. Check also to make sure that he has no blemishes discoverable by an internet search or at least no blemishes sufficient to give him too uncomfortable a time in cross-examination.
It is as simple as that. In fact, it is.
Having an expert witness who is in truth an expert and straight is a large part of the battle.
Test that view against the way in which one cross-examines experts.
First one looks at their qualifications. Are they in truth experts? Are there areas that have given evidence about that are outside their expertise? How does their expertise compare with the expert on the other side?
Have they over-egged their qualifications? (A good start to any cross examination if they have…) Have they failed to draw attention to some lacuna in their expertise? Have they failed to follow the rules of Court about the content of their report? Have they drawn attention to points potentially adverse to their opinion? Have they identified all the sources upon which they have relied?
In oral evidence do they make concessions quickly enough? If they do make concessions, why were their concessions not made in their report or in the expert’s agreement?
There is nothing as good as a good expert and nothing as bad as a bad one. Trite but right.
If experts do not do their job properly or misrepresent their position then they badly harm the party whom they are instructing. Having a bad expert or one who does not follow the rules harms your case.
When giving oral evidence, experts have to tread a fine line. They have to be truthful and honest and remember that they are witnesses and not advocates. However, they need to be able to “hold their own” and explain fully truthfully, honestly and persuasively the views that they have.
We have all seen the full range of experts. The expert who pretends he is more expert than he really is and by the time he appreciates his error is in too deep. The expert who forms a preliminary favourable impression of his client’s case and then again in too deep to row back when he discovers things that would have caused him to qualify his opinion. The expert who gives in to pressure from those around him to be more favourable to the appointing party then he ought to be. The witness who is belligerent when cross-examined and who destroys his own creditability. The witness who falls apart when cross-examined and actually ends up doing more damage to his appointing party’s case.
Over the years I have seen some expert witness disasters. Probably the one who sticks in my mind most is the expert who when asked whether this was his report and whether it contained the views he held in relation to matters in issue answers that depended upon whether the question related to now or when he wrote it. It had been true when he wrote it but now as a consequence of something that he had just discovered it was all completely wrong. Or the witness who when re-examined was asked to confirm his original views said that he had changed his mind in cross-examination as a result of the questions from Mr X. (not me !). Or the witness who, after some powerful cross-examination, accepted that his performance as an expert had been a disgrace.
And I have seen some absolutely brilliant ones. Thorough, fair, balanced, courteous and assured and who did not put a foot wrong.
At the risk of repetition, get the best expert you can, ensure he understands his role and complies with the rules and jealously guard his independence. He will be your best weapon.