Deputy Assistant Commissioner Martin Hewitt, the national lead for adult sexual offences, says victims must be encouraged to report incidents but also have a right to expect a more honest approach to discussions about the realities of prosecuting rape claims.

"We need to be honest about the challenges that are faced in investigating and prosecuting rape," said DAC Hewitt.

"Police will do everything they can to ensure that victims get the support they need when reporting a rape or sexual offence."

"We will thoroughly investigate the offence and put all our efforts into ensuring justice is done. We want to support those who are victims of these crimes and do all we can to increase reporting levels.

"The conviction rate is at an all-time high and this is down to the hard work of police, prosecutors and other agencies working together to develop victim focused approaches and take cases through the courts. But, despite the bravery and tenacity of the victims who do go through the process, a third of rape prosecutions still don't end in a conviction."

"That can put people off reporting because they think it isn't worth it. I really want to show people this week that victims should have the confidence to report. It triggers a full investigation into the offence, but also means that victims are able to access medical treatment and support services to help them cope with the experience."

In 2012/13, 3,692 rape prosecutions were brought with 63.2 per cent of these cases resulting in convictions; a 5.5 per cent increase from 2008/9. Reporting of sexual offences to the police is also up 9 per cent this year; the largest increase since current recording standards began. The public debate about sex offences, particularly non recent child abuse, may have been responsible for this increase.

Jordan Hart, an 18 year old rape survivor whose attacker was jailed for 11 years, has waived her anonymity to support the campaign and encourage more women and men who are victims of rape to report it to the police:

"Reporting to the police gave me peace of mind, knowing I hadn't been beaten by him. I was supported by my SOIT officer who gave me advice, guidance, explained what was going to happen and how long it would take; I didn't do anything alone."

During the week of 2-6 December, police forces will be running targeted campaigns focussing on communicating how they deal with rape and sexual offences, the support victims should expect and the realities of the judicial process into this type of claim. DAC Hewitt will also be taking to Twitter to answer questions about how the police can better deal with this type of crime directly.

The last six years have seen significant improvements in the police response to sexual offences; specialist training of officers, the introduction of early evidence kits, greater access to sexual assault referral centres, and working closely with support groups.

DAC Hewitt also called for people to take the debate on prevention of sexual offences seriously:

"The debate is far too often restricted to investigation and prosecution; I am very keen that we do all we can to tackle rape and that means generating a challenging debate about prevention as well. Most rape involves the coming together of some form of power and some type of vulnerability; either permanent or temporary. We need to be using all our powers and tactics to understand how this happens, to mitigate the vulnerability and reduce the opportunities for that power to be abused. I am keen to talk about how this can be done."

To report a sexual offence or rape to the police, call 101 or 999 in an emergency.