A college student who accused Nelly of rape has asked police to stop their investigation.
In a statement, the woman's lawyer, Karen Koehler said: "She wishes she had not called 911 because the system is going to fail her."
Nelly was arrested last week after a woman said he raped her on his tour bus in a town outside Seattle.
The rapper whose real name is Cornell Iral Haynes, Jr. has always denied the claims.
Karen Koehler posted the full statement on her personal website.
As well as announcing that her client will not be testifying she suggested the legal process had let the accuser down.
She wrote: "We do not live in society where a 21-year-old college student can feel safe enough to pursue criminal charges against a celebrity for an alleged rape."
"Not because what happened didn't occur exactly the way she described," Karen Koehler said.
Karen Koehler went on to say that the alleged victim had decided to drop the case due to the unwanted attention she was receiving since filing charges against the star.
Nelly has always denied the allegations against him and his lawyer, Scott Rosenblum said news of the letter was "welcome".
He added: "Her reckless accusation, once investigated thoroughly, was exposed for what it was, a fabrication.
"I am suggesting that Nelly seeks a public apology. Nelly thanks his fans for their unwavering loyalty."
Nelly, who recently released his seventh studio album M.O. is due to play 15 shows around the UK starting in November.