Nazanin Zaghari-Ratcliffe, who was detained by the Iranian government for six years, has called for indefinite prison sentences with no clear end date to be fully abolished – telling the Labour party conference that her ordeal and what people with indefinite sentences experience are not so different.

The indeterminate sentence of imprisonment for public protection (IPP), introduced in 2005, were designed to prevent offenders considered dangerous from being released even though the offence did not merit a life sentence. However, IPP sentences were criticised for catching less serious offenders. When they were abolished in December 2012, the change was not applied retrospectively. According to campaign group UNGRIPP, 2,486 people are now in prison on an IPP sentence; 94 have killed themselves in prison.

Akiko Hart, director of human rights group Liberty, said IPP keeps people in prison 'for something they might do in the future rather than what they did in the past', which 'goes against every cornerstone of our justice system'.

One ex-prisoner told the conference that people would be recalled to prison because they were deemed a risk - but in reality, they may have missed a couple of probation appointments 20 miles away but they had no money to get to.

Zaghari-Ratcliffe told the conference that her experience of detention resonated closely with what IPP prisoners have gone through.

Nazanin and Akiko

Nazanin Zaghari-Ratcliffe and Liberty director Akiko Hart discussing IPP sentences at the Labour party conference

Source: Monidipa Fouzder

When she was temporarily released and required to wear an ankle tag, she would get calls in the night because the tag would wrongly show her not being at her parents' house. ‘The fear and anxiety that any phone call would mean I would be called back to prison. In my semi-freedom I was not actually free. That’s alienating and isolating. It makes you not be willing to leave the house because anything you do might pull you back into prison.’

Calling for IPP sentences to be abolished, she said: ‘Every single day you are keeping them longer in prison, you are risking their mental health but also, frankly, their lives.’

Following an inquiry, the House of Commons justice select committee concluded that the only way to address the IPP problem was to enact primary legislation so that a resentencing exercise could be carried out for prisoners still serving or on licence for an IPP sentence. Resentencing could be added to the Sentencing Bill currently going through parliament, the event heard.