Dr. Robert Anderson, Assistant Commissioner of the Metropolitan Police and Chief of the Criminal Investigation Department (CID), placed Swanson in overall charge of the investigation into the Whitechapel Murders from 1 September to 6 October 1888.

Swanson was freed from all other duties and given his own office at Scotland Yard from which to co-ordinate inquiries. He was given permission to see “every paper, every document, every report and every telegram” concerning the investigation.

In this way Swanson gained a mass of knowledge and information about the killings.