A SEX ATTACKER who tortured and raped four women over two decades will spend at least 10 years behind bars.
But judge Bill Dunlop QC told John Walker: "You are classed as a high risk of re-offending and you may never be released.
"There have been a series of depressing cases lately where men have used, abused and brutalised women."
Judge Dunlop told Walker that the lifelong restriction order meant it was up to the parole board when, if ever, he is released.
Walker, 49, battered and abused his terrified victims - including one pregnant woman who was attacked with a pole - in Glasgow and Clydebank.
He also shoved another girlfriend into a coal fire before going on to rape a 16-year-old girl.
Walker evaded justice for years until a daughter of one of his victims reported him.
In the middle of his trial at the High Court in Glasgow, he admitted to five rape charges and four of assault spanning from 1988 to 2009.