 Stevenson became a High Court judge in 1957, and acquired a reputation for severity in sentencing.He sentenced the Kray twins to life imprisonment in 1969, with a recommendation that they serve not less than 30 years each.In 1970 Stevenson passed long sentences on eight Cambridge University students who took part in the Garden House riot, and the following year gave Jake Prescott of the Angry Brigade 15 years for conspiracy to cause explosions.