"Deception detection" experts—often former CIA agents—are used by banks and hedge funds to assess the honesty of CEOs. In his recent book, Broker, Trader, Lawyer, Spy, Eamon Javers shares some tricks of the trade:
Aside from true sociopaths, people aren't natural liars, and saying one thing while thinking something else can actually cause physical discomfort. That's what causes people to squirm.
2. Weasel Words
Expected to, probably, basically, should be... These kinds of qualifiers crop up when someone is trying to obscure doubts or worries.
3. Detour Phrases
Think, As I said before. Liars try to circumvent a direct answer by referencing past answers to different questions.