The kidnap and murder in November 2000 of 16-year-old Leeds schoolgirl by John Taylor, described at his trial in 2002 by the judge as a "sexual sadist".[6][7] In February 2003, he was convicted of two rapes, based on DNA evidence, and given two additional life sentences.[8]
Leanne Tiernan
The American fugitive who murdered traffic PC Ian Broadhurst and attempted the murder of two other policemen on 26 December 2003.[9][10][11][12][13]
David Bieber
Identification of the Hoaxer, John Humble, who was tried and sentenced in October 2005 – 25 years after the offence which was one of the most notorious – and damaging – hoaxes in criminal history.[14][15][16][17] Gregg won £50,000 libel damages, plus costs, after being accused by Irish writer Noel O'Gara of "stitching up" John Humble as the writer of the hoax letters and sender of a tape recording purporting to be from the Yorkshire Ripper.[18][19][20]
Yorkshire Ripper
Serial killer , dubbed the 'Angel of Death' who murdered four elderly patients in a hospital in Leeds, receiving a life sentence in 2008.[21][22][23]
Colin Norris
Gregg led the enquiry into the deaths in West Yorkshire, when Shipman, a practising medical doctor, was apprehended, later having 218 murders positively ascribed to him.[24]
Harold Shipman
In his career, headed some high-profile criminal investigations including:
On leaving the force he spoke against the misuse by suspected murderers of the protective shield of human rights legislation.[25][26][27]
2008: Gregg was awarded the Queen's Police Medal (QPM) in the 2008 .[28]Chief Constable of West Yorkshire, Sir Norman Bettison, described Gregg as one of the finest detectives the force had ever known.[4][29]