The illegal status of sex work creates conditions in which exploitation and abuse can thrive. Sex workers and brothel owners could be an important source of information for the police about abuse in the industry, including human trafficking. But because sex work is criminalized, they tend not to be open with the police.
Sex workers experience various forms of physical abuse violence and corruption at the hands of police. Some of them have been threatened with violence by the police; others have been forced to have sex with police officers (i.e. raped), others have been asked for sex for sex by policemen in exchange for release from custody.
The relationship with the police clearly does not encourage sex workers to report cases of abuse or exploitation. The consequence of this is that sex workers, who are already vulnerable to abuse by the clients and other third parties, are made even more vulnerable.