By Dr. Ken Broda-Bahm:
As the question hangs in the air, you can see the tension working on the witness. Her face screws up, she looks at the ceiling, tenses her shoulders, and delays. As you call for a time-out in the preparation session, the witness blurts out, "What should I say? I don't know the answer!" Well, the attorney and consultant patiently explain, if you don't know, then perhaps that should be your answer. As long as the witness has done her homework in knowing what she should know, and as long as she isn't using it as an evasive tactic, then "I don't know" is going to be the only correct answer to that question. For attorneys and those who work with them, that advice is pretty obvious. Only it isn't always so clear on the witness's side of the table. Saying "I don't know" can feel like failing a test, looking stupid, or falling into opposing counsel's trap.
A key message for witnesses to take from the preparation process, however, is that there is great power in "I don't know." When it is used thoughtfully and accurately, it is one of many ways to keep the other side from gaining what they have not earned. When the witness doesn't know, and when the witness shouldn't be expected to know either, then being comfortable and confident in one's "I don't know" will make for a harder examination and fewer mistakes. As simple as that advice is, the subject might benefit from more than the top-level explanation. After all, the fact that it is such a common temptation suggests that there are powerful forces pulling witnesses away from the safety of their own knowledge. In this post, I will take a quick look at why witnesses sometimes avoid the "I don't know," some of the ways they try to avoid it, and a few alternative ways to say it that might be more comfortable.