On Monday 5 January 1981, Sutcliffe appears at Dewsbury Magistrates Court.After explaining his prostitute killing as following God given orders, police are satisfied that Sutcliffe was suffering from paranoid schizophrenia and should be incarcerated in a secure mental institution.
A judge decides, however, that Sutcliffe will face trial. He wants to give a jury the right to decide whether Sutcliffe is insane.
His brother Carl visits him in jail and like Sonia, just wants to know why his brother has caused so much pain and suffering. Peter Sutcliffe’s replies;“Oh, just cleaning up our kid, just cleaning up.”
Four months after confessing, Sutcliffe’s trial commences on 29 April 1981.

It lasts a fortnight. His detailed confession and plea of insanity mean the jury are instructed to determine his mental state, rather than his guilt or innocence.
Throughout it all, Sutcliffe shows no emotion.
“He came up from the cells in the morning, took his seat in the dock just as though he were arriving in the office for work.”-Henry Matthews, Former Journalist
On 22 May 1981, after six hours of deliberation, the jury give a majority verdict of 10-2 finding him sane. They find Sutcliffe guilty of thirteen counts of murder and the attempted murder of seven others.The judge sentences Sutcliffe to life for each murder and recommends a minimum tariff of thirty years.