WASHINGTON There were 88,097 rapes in the United States in 2009 alone, according to FBI statistics, but the crime remains one of the least reported and prosecuted, witnesses told US lawmakers on Tuesday.

“It's widely recognized that rape is one of the most underreported offenses in the United States with empirical studies estimating that merely 15-20 percent of cases are reported to the police,” Michelle Dempsey, a professor at Villanova University School of Law told senators.

Roughly one in six women in the United States will experience sexual aggression during their lifetime and half of the victims were younger than 18 at the time of the assault, an investigation presented to a subcommittee of the Senate Judiciary Committee said.

Only five percent of rapists are convicted and only three percent are imprisoned, Eleanor Smeal, president of the Feminist Majority Foundation, told the committee.

“Fifteen out of 16 rapists in America will walk free,” said Scott Berkowitz, president of the Rape, Abuse and Incest National Network. That comes despite the FBI's classification of rape as second only in seriousness to murder.

Experts said a range of factors make rape difficult to prosecute, including the way it is defined, victims' fear, their desire to avoid humiliating witness testimony, and unsympathetic or incompetent policing.

The 1927 Uniform Crime Report (UCR) classifies rape as “the carnal knowledge of a female forcibly and against her will.” But it does not include statutory rape, incest, forcible sodomy, assault with an object and other forms of equally traumatic sexual violence.

“The upshot of this narrow definition is that many rapes are excluded from the UCR statistics,” the Feminist Majority Foundation said. The figures also count victims but not the number of rapists.

Underreporting also makes it difficult to tell how many assaults are taking place, experts said.

“Victims do not report because they fear that their report will not be taken seriously, they will not be believed or they will be seen as responsible for their own assault,” said Carol Tracey, director of the Women's Law Project in Philadelphia.

That was what happened to Sara Reedy, 25, who was attacked by a serial rapist in the drugstore where she worked when she was just 19.

When she reported the crime, she was accused of stealing and making up the assault. She spent five days in jail and was released on 5,000 dollars bail, but was only able to pursue her attacker when he admitted he had raped her during an interrogation after being arrested for a separate crime.

Julie Weil, kidnapped and raped in front of her children in 2002, described the opposite experience, saying a team of investigators listened to her story and helped heal her wounds by prosecuting her attacker.

“In the immediate aftermath of the trial I realized that closure is not a myth. There is immense power in seeing a case through to the end for a victim,” she told lawmakers.

“Seeing my rapist led away from the courtroom in handcuffs was more gratifying that I ever thought it would be.” - AP