RETIRED detective Dick Holland has defended the decision to concentrate on a man with a North East accent in the hunt for the mass killer.
Mr Holland, of Huddersfield, spoke out as John Humble admitted perverting the course of justice by writing letters and sending a tape claiming to be the killer.
But Mr Holland, who was second-in-command of the Yorkshire Ripper inquiry in the 1970s, has defended the decision to focus on the Wearside Jack letters and tape.
Former Det Supt Dick Holland admitted the inquiry team made a serious mistake by not separating the murder inquiry from the investigation into `Wearside Jack.' But he believes detailed information contained in the letters provided a compelling case to take them very seriously.
Mr Holland, who is now 73, said the criticism levelled at his boss, George Oldfield, formerly of Grange Moor, for devoting so much effort to the voice on the tape was nothing compared with what would have happened if they had not taken it seriously and it had been genuine.
"There were some mistakes made that had fairly serious consequences," he concluded.
"I've never made any secret of that.
"But, with very few exceptions, everybody worked hard and honestly, " Mr Holland said.
The retired detective admitted he was surprised when he heard about Humble's arrest.
"I was just shocked when I heard. I suppose I just thought it was one of those things that would just remain unsolved."
Mr Holland continued: "If we hadn't done and something in it had been right, we would have come in for even more criticism ."
Mr Holland said the obvious effect of the letters and tape was to waste a huge amount of resources.
But he added it was wrong to conclude the distraction led to the avoidable deaths of the Ripper's final three victims.