The person can tell the plice that they don't want to pursue it but its up to the police whether to make an arrest. If the person tells the police that the charges were not true the person could be arrested for making a false police report.
I am a former federal and State prosecutor and now handle criminal defense and personal injury/civil rights cases. Feel free to check out my web site and contact me at (212) 385-8015 or via email at Eric@RothsteinLawNY.com. The above answer is for informational purposes only and not meant as legal advice.
The person can make their feelings know to the prosecutor, judge and to the lawyer of the accused. However if the person now says that (nothing) happened after telling the police that something did, they may face criminal charges for falsely reporting an incident.
I am a former Deputy Bureau Chief with the Brooklyn District Attorney's Office who has been specializing in criminal law for over 15 years. I offer free consultations by telephone, in-office or by videoconference.
All answers are for information purposes only. Answering this question or any future questions does not form any attorney-client relationship. Be mindful, that answers are limited by the limited facts presented by the questioner and are not meant to take the place of competent legal advice by an attorney fully informed of all the facts surrounding your case. However, be aware that nothing posted in a public forum such as this can be deemed confidential or privileged communication. For a privileged private consultation, contact me at 212-385-8600 or via my website www.reasonabledoubtny.com