A journalist at The Times had a question for me yesterday. What do you wear when your name is Tony Blair and you are about to be grilled by the Chilcot inquiry?

When we dress in a way that supports what we are saying, our message is reinforced and we are more likely to be believed. When we dress in a way that is not compatible with our message, the reverse is true.  So how did he need to dress?

Firstly, what was his message? What did he want to convey?  Honesty, authority, to look like he cared. He also wanted to convey  genuine heartfelt belief and the sense that if we had been in his shoes, we would most likely have done the same.

The next question is what does the audience expect? That he looks like a former prime minister, that he looks in control, not only of the facts, but also of himself.

He was well advised to wear the uniform of power; high-contrasting and authoritative white shirt, dark suit and red tie.  The clean white shirt suggesting nothing to hide, and a red tie giving authority. Properly fitting clothes and excellent grooming reinforced these messages. This is also about conveying respect to your audience. Going tieless was not an option.

His voice sounded husky, strained, perhaps an indication of the personal tension he was under. As for his body language, no arms crossed in defiance, but hand gestures used to reinforce a point and good eye contact with the panel. Initially tense, hands shaking as a sign of nerves and pressure, his audience might be reassured by such human signs.  He heeded other advice: don’t raise your voice; don’t lose your cool; answer the questions to the panel’s satisfaction.  It’s not a time to evade the question, be heartfelt.

Verdict:  Whether you agree or disagree with his decision making process, Tony Blair achieved his aim. He looked his best to be believed.