The opening statement is your first comprehensive opportunity to start to win your case. And, unlike the vast majority of the trial, the opening statement is focused on the lawyers. It is the first time the finder of fact will be able to observe your presentation, hear your overview of your case and evaluate your credibility. Simply put, it is one of the few times you will communicate directly, plainly, persuasively, and candidly with the fact finder - whether it be the judge or the jury.
Of course, you must be circumspect and somewhat cautious not to cross the lines by violating one or more of the generally accepted principles of opening statements. So, do not preview inadmissible evidence; do not embellish; do not argue the law; do not argue the facts, indeed, do not argue; do not vouch for your client; and leave the untested to be tested some other time. Equally important, every courtroom, arbitral panel and judicial body has its own spoken or unspoken rules of decorum. It's your job to figure them out before your begin.