Last year, a man died when he was extradited by force from Sweden. According to the medical examiner in the case, the way he was restrained, while being agitated and in a confined space, contributed to his death from lack of oxygen.
The guards who used the method, were initially suspected of manslaughter and breach of duty, but the preliminary investigation into the case was dropped when it emerged that they had only been following instructions from the Prison and Probation Service.
But already in 2011, a study was published that showed "significant reduction in lung function" if a person is pressed on their upper torso and/or in a flexed position.
"I would just basically say: 'don't do that'. Don't push people forwards. And I would not train people to do that," professor John Parkes, one of the authors of the study, told Swedish Radio's investigative programme Kaliber.
Following the reports in media, the Prison and Probation Service has decided to review the methods they are using. But in the meantime, the method of pushing a person forward is still being used, says Jonas Lexell, at the authority's unit for developing methods for safety training.
"Yes, it is," he told Kaliber.