"It is a variety of 36 stories for people who are interested in human nature and what makes people tick."
The subjects of his reminiscences include his friend "Jim" - poet James K. Baxter - and people he defended and represented during his 60-year career, including Ronald Jorgensen, Arthur Allan Thomas, "Mr Asia" Terry Clark and New Zealand First leader Winston Peters.
"I have had the privilege of being in touch with a great variety of people in a variety of situations," Sir Peter said.
"I have learned to be humble and I have learned to listen - to listen to the other side and hear what their explanation is.
"Some people are so traumatised by their situation that they really have difficulty in enunciating what their side of it is.
"There is a story of a man who chopped his companion's head off; I explain it all and why it happened.
"There is a woman who killed her child and me listening to her in prison and her situation and the unfairness of the prosecution."
In his book, Sir Peter also recalls being a university student doing a casual labouring job, with Baxter.
They unloaded cement from ships on the Wellington wharves and socialised after work.
"I began to realise I was in the company of a 'distinguished intellectual and poet'."
The country's biggest festival of words and ideas opened yesterday and concludes with a Family Day on Sunday.
On today
Comics 10, with Ant Sang, Goodman Fielder Room, Aotea Centre, 9am to 10.30am.
A Law Legend: Sir Peter Williams, Lower NZI Room, Aotea Centre, 10am to 11am.
Lucky Us: US writer Amy Bloom discusses her novel, ASB Theatre, 10am to 11am.
Gallipoli and Other Stories: Peter FitzSimons, ASB Theatre, Aotea Centre, 1pm to 2pm.
Buy Me The Sky: Chinese writer Xinran discusses her latest book about the impact of the one-child policy, ASB Theatre, Aotea Theatre, 2.30pm to 3.30pm.
Hack Attack: British author and journalist Nick Davies, who uncovered the News of the World phone-hacking, joins Herald columnist Toby Manhire to discuss the media; ASB Theatre, Aotea Centre, 4pm to 5pm.
An evening with Alan Cumming, ASB Theatre, Aotea Centre, 7.15pm to 8.30pm.
See writersfestival.co.nz for more information.