When you deal with a business like mine, you actually have to trust us with a lot of your secret. If you come to us to defend you in a court case where you might go to jail if you lose the case, you better tell us the truth. As what I have posted once, the first question a lawyer should ask, which you can read here. Whether you really kill that guy. Whether you really steal that bike. Whether you really had consensual sex or you forced yourself on her. If it is a civil case, why you don't want to pay the person who says you owe him money. Or why you don't want to finish the job that was entrusted to you. All these are questions that we as lawyers are going to ask and you as the client, will need to enlightened us.
However, this is not the trade secret which is important for lawyers. All these are clients' secret which are actually protected by the attorney-client privelege. There are laws for that. What lawyers should be worried about is how to tackle the cases presented in front of them. How agreements are struck. How certain trials are conducted. Questions in court which will turn the tide in favour of their client. The way you pose a question until an uncooperative witness breaks down and tell you all that needed answered.
All this are trade secrets of lawyers and it is not easy to steal as it is usually in the head of the lawyer who had been to various negotiations, various trials and even various talks. If they had put in place a succesion plan in their office, usually this skill will be passed to that person. However, once, I have seen one of my friends who worked with a medium sized legal firm took away with her nearly 10 volumes of precedents in the form of agreements when she quit from the firm. That is why after we had our own firm, we also copied all the work that is done in our staff computer, just in case we need to find all the precedents which we know can help us sometimes in the future.
That trade secret worth quite a lot, if you asked me.