withdrawing a statement

[stuartsmith]

a friend of mines wife recently acussed her partner of a sexual assualt she later withdrew her statement but the cps are still going ahead with the case the police contacted her to let her know what was happening and she asked if she could change her statement as she no states that there was no sexual intent involved but the police officer said that she could not do this now is this correct or can she change her statement at any time regardless whether it has been withdrawn

[Buenchico]

The policy of the Crown Prosecution Service is that, in cases of domestic violence (which includes sexual assaults upon a partner), they will normally use a victim's statement in court, even if the victim later tries to retract that statement. So, whatever your friend's wife now says, the CPS can still use the original statement in court:
http://www.cps.gov.uk/publications/docs/Domest icViolencePolicy.pdf

So the statement can't be withdrawn, as such. Of course, your friend's wife could make a second statement, refuting the first one, but that would lay her open to one of two possible criminal charges:

Firstly, if the police and CPS were of the opinion that the original statement had been a lie, she could be charged with wasting police time.

However, if they were of the opinion that the original statement was true, and that she was now refuting it in order to prevent her husband being convicted, she could be charged with the far more serious offence of 'attempting to pervert the course of justice'. (Such a charge, upon conviction,nearly always leads to a lengthy prison sentence).

Chris