"If you look at prisoner surveys some say they have shared needles in prison. There will always be people who continue to take drugs in prison," a SPS spokesman told BBC. "If you're not going to change that behaviour and have people who are going to do this, we have a responsibility to them and to make sure that our staff are safe. Aberdeen prison does have a high proportion of people on drugs coming into the prison."
Scottish Conservative leader Annabel Goldie MSP said that the jails system needed urgent reforms. "We should be helping prisoners get off drugs, rather than help them take them," she said. "This measure does rather suggest that a damage limitation exercise is being deployed, rather than any real drive to get drugs out of our prisons."