The majority of sex workers are women,  and most rhetoric rests on the assumption that the sex workers being discussed are women, while the buyers are men. The majority of sex workers suffer from violence while working in their lifetimes. 
The sex industry continually meets the desires of customers. Transactional sex is often violent and abusive, fulfilling base desires that may not otherwise be considered acceptable. Prostitutes are often the victims of abuse or murder. The death rate of sex workers is more than 40 times that of the general population, and the majority of sex workers in a five-country report were found to have suffered from physical, emotional and sexual violence over the course of their careers. As violence is so innately linked to prostitution, any state sanctioning of prostitution is essentially the state sanctioning of violence against women.
The criminalisation of prostitution perpetuates violence against women by making sex workers unable to report violence against themselves through fear of prosecution. Many sex workers suffer violence at the hands of police when reporting violence. By criminalising prostitution, rather than offering the victims of violence the opportunity to get help, governments are trapping victims and increasing their vulnerability.
[P1] Violence against sex workers is innate to prostitution. [P2] Therefore, to decriminalise prostitution is to legalise violence against women.
[Rejecting P2] Criminalising prostitution makes prostitutes more vulnerable to violence.