“Do you promise that your testimony will be the truth, the whole truth—so help you God?” I was sworn in as an expert witness at a trial last week (I’m asked to do so several times each year). Once again, I was asked to swear to a God I don’t believe in. I said yes (it’s part of the job), but doing so always makes me cranky (and having to wear a suit while saying it doesn’t help my mood). Some U.S. courts ask you to simply swear or affirm to tell the truth, but I’ve always been asked to…