Women's organisations have said that sexual offence cases are being dropped without good reason and they are prepared to go to court to prove it.
The group, represented by the Centre for Women's Justice (CWJ), is crowdfunding to support its claims, which it says are based on more than 20 cases recently discontinued by prosecutors.
They accuse the Crown Prosecution Service (CPS) of changing its policy when deciding whether to prosecute rape cases.
Sarah Green, End Violence Against Women (EVAW) coalition coordinator, said: "We have strong evidence to show that CPS leaders have quietly changed their approach to decision-making in rape cases, switching from building cases based on their 'merits' back to second-guessing jury prejudices.
"This is extremely serious and is having a detrimental impact on women's access to justice.
"In the justice system there are well-known myths about rape, but prosecutors are supposed to deal with them – not just say 'we can't expect a jury to disregard it'.
"We're not just a shouty group saying 'Let's have a go at the state'. But the refusal to listen and to implement what we say is a massive change for the way these cases are brought to court – we say, for the worse – is the reason why we have taken these measures.
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"If necessary, we will end up in court opposite the CPS and will have to let judges decide whether we have a case or not."
There was a 23.1% drop in the number of rape cases taken on by the CPS in the 2017-18 year, despite a 16% increase in rape reports to police over the same period, according to government figures.
Harriet Wistrich, CWJ director who is bringing the case for EVAW, said: "We are arguing that the CPS's systemic failure to prosecute rape is a comparable human rights failure and has a discriminatory impact on women, who are the large majority of rape victims."
Katie Russell, national spokeswoman for Rape Crisis England and Wales, said rape survivors "tell us they include fear of being re-traumatised through what can be a very long and difficult process, with little prospect of seeing their perpetrator brought to justice at the end of it".
The women's coalition is to submit a "letter before action" to the CPS later oRead More – Source