9 Ways to Prove Sexual Assault Without Physical Evidence
Investigators don’t always need forensic evidence to prove a sexual assault occurred.
This article, originally published in Oct. 2017, was updated in Feb. 2022 to reflect current research and statistics.
If you are a victim of sexual assault, you can call the National Sexual Assault Hotline at (800) 656-4673 or chat online at online.rainn.org for help. Additional resources for victims can be found here.
Investigating college sexual assaults is a sensitive process, and to actually prove a sexual assault occurred is an extremely difficult task.
Why can sexual assaults be so difficult to prove or disprove? Unfortunately, there are a number of reasons.
The National Sexual Violence Resource Center estimates 63% of sexual assaults aren’t reported to the police, so just getting the victim to make an official report is the first hurdle, and getting them to follow through in the investigation and adjudication phases can also be a challenge.
One study found that 90% of sexual assaults are committed by someone the victim knows, which can lead to confusion on the part of the victim and reluctance to pursue justice.
According to the U.S. Bureau of Justice Statistics, abuse or assault is:
- Least likely to be reported if the offender is a current intimate partner or former partner (only 25% of these assaults reported to police)
- Less likely to be reported if the offender is an acquaintance or friend (only 18-40% of these assaults reported to police)
- Most likely to be reported if the offender is a stranger (46-66% of these assaults are reported to police)
Additionally, a study from the U.S. Department of Health and Human Services found more than 50% of college sexual assaults involve alcohol, which can affect recall and make the victim fear being punished or feel shame.
Witnesses can also be hard to come by in sexual assault cases generally, and in college specifically because of the prevalence of large, unsupervised parties. Students tend to be at a higher risk at certain times of the year. For instance, more than half of college sexual assaults happen in August, September, October, or November, which is consistent with the first few months of the first semester.
But experienced sexual assault investigators can find ways around all of these hurdles, and justice can be brought even in sexual assault cases without much initial evidence. 
New Title IX changes relating to the college sexual assault investigation process might mean different campuses are using different standards, but every college still has the same goal of keeping their students safe and comfortable.
In May 2020, a serious roadblock for sexual assault investigations was implemented when the U.S. Department of Education implemented a new rule for Title IX investigations. The new rule prohibited decision-makers in sexual misconduct investigations from using evidence or statements from someone who did not participate in cross-examination at a live hearing. This received significant criticism from advocates for sexual assault survivors way believe live questioning could re-traumatize victims and prevent victims from coming forward.
In Sept. 2021, the rule was rescinded, allowing decision-makers to consider evidence from involved parties who did not undergo cross-examinations, including police reports, medical reports, Sexual Assault Nurse Examiner documents, and emails and text messages sent leading up to the alleged misconduct.
Below we give some best practices for campus police to get to the bottom of any sexual assault report, even with limited or no physical evidence. The information is adapted from The Blueprint for University Police: Responding to Campus Sexual Assault, which focuses on giving law enforcement information on handling rape and sexual assault cases.
Trauma-informed practices, which involve recognizing, understanding, and properly responding to the effects of trauma, are becoming more commonplace during police investigations.
The need for trauma-informed investigations is critical since a 2021 survey from Know Your IX, a survivor- and youth-led advocacy group, found educational disruptions for students who reported their sexual assault to their schools were not from the sexual violence alone, but because of violence exacerbated by schools’ harmful responses to reports of violence. 
A study conducted by the Salt Lake County Sexual Assault Response Team (SART) determined applying a trauma-informed approach to sexual assault investigations led to more charges being filed and more successful prosecutions.
When a victim feels supported and protected, they are more likely to participate in an investigation and therefore more likely to provide useful information beyond physical evidence.
Searching for Proof During Sexual Assault Investigations
At first, sexual assault reports can appear to be “He said, she said” scenarios, where there are little investigators can do to corroborate the accused or accuser’s stories. Unfortunately, experienced sexual assault investigators are familiar with these scenarios.
There can’t always be forensic evidence to work with, but police can still prove sexual assault occurred or didn’t occur with little to no initial evidence, even in cases where there are no witnesses. Here are nine tips:
- Practice interview techniques such as victim debriefing and adapt an “information gathering” versus interrogation approach to suspect interviews to gather information. Understand physical descriptions (e.g. tattoos), smells and sounds the alleged victim remembers. Here are more facts and myths on sexual assault that police should know.
- Document the specific details of the allegations, all the way down to condom use.
- Gather circumstantial evidence during the investigation, such as a sudden behavior change from the alleged victim. Look for dropped classes, withdrawal from sports or social clubs, and a sudden change in academic performance.
- Try to establish elements of force, threat, or fear if present from either party.
- Look for a serial pattern of behavior from the accused by contacting others who may have been victimized by that person, while being careful not to marginalize the accused.
- Conduct an extensive investigation for corroborating evidence including social media and cell phones.
- Evaluate the need for a search warrant.
- Consider the utility of a pretext phone call to gather evidence from the accused.
- Identify and contact any outcry witnesses.
The above information is adapted from The Blueprint for University Police: Responding to Campus Sexual Assault.
If you are a victim of sexual assault, you can call the National Sexual Assault Hotline at (800) 656-4673 or chat online at online.rainn.org for help. Additional resources for victims can be found here.
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1. can be difficult to disprove
the accused doesn’t have to disprove it. until the accuser proves it, he is innocent
imagine a society where accused have to prove they didnt commit a crime
2. try to establish elements of force, threat, or fear from either party
this should be pretty self-explanatory why this isnt supposed to happen
3.if there was a rape, DNA could easily prove if it happened or not.
even if they used a condom, it will still show. everywhere you go, everything you do, you leave some type if DNA. hair, skin, etc…
its not perfect. maybe it was consensual at first but if we start with this, we can figure out if it even happened or not. after it has been determined it DID happen, you now at least know the evidence to determine consent exists somewhere
4.rape is unwanted PHYSICAL sexual contact. everything else is bullshit
and yes, some people do IN FACT believe “over the internet rape” is a thing
the fact that needs to be clarified is kinda sad
EDIT:
*the fact that this needs to be clarified*
as i read your comment there have been hundreds of women that claimed to have been sexual harassed or assaulted 5 to 20 years ago and have NO PROOF or physical evidence of it and yet the men are being sued and going to jail etc… We live in a society that has allowed women to lie just to get money and has left real women in real life situations that are being beaten and raped for REAL and they can no longer be trusted because we don’t know if it’s real or not… I am a woman and I am disgusted by how many women (ugly women at that) that are lying against rich men just to get money in their pockets. it is sickening
I believe it is close to impossible for a victim to be able to come forward about their rape after a couple months…definitely after a year
It’s relieving to know that there are experts out there that can really help your case even if there are no physical pieces of evidence available. I will share this information with a friend of mine to make her feel better since she really feels like she’s going to lose if ever she files a case. From what I know, one of her colleagues is really creeping her out because the actions and the words that he was using on her is already bothering her. Thanks for the information!
Rape is a horrendous experience and though the police won’t follow any leads the victim will be pursued for years by extortionists. It is a dangerous situation and something should be done to make the government prosecute rapists.
Rape is a horrible experience with out cause and even more frightening not knowing who it is, remarkable there’s hope thank to medical expertise we have a rape kit hope that enough in 2019. were lookin into a new era with a new battle we must be prepared like our dear writer Joyce Meyer our mind are instrument of peace and war.
We cannot be a society where people can be ruined and even incarcerated on accusations alone. I personally know a man going through this. The accuser is a spiteful angry teenage girl and even laughs about the fact she doesn’t have to prove anything. She says because of the me too movement, authorities have to believe her. I know both of these people and I don’t believe her for a minute but the man has been ruined financially, spent 3 months in jail and is facing a trial with possible prison time.
I looked this up because I’m going through it right now I came forward with my story and they are working it out right now but the fact that people can protect people like that is discussing to me I get it it’s their job but protecting a rapist and somebody who assaults girls and guys is just wrong.
The issue is not whether to believe or not believe; always believe because rarely does a person/child make up a story of sexual abuse. What concerns me is when you have happened what happened to me, which definitely puts law enforcement in a difficult/delicate spot, not to mention family.
I have an adult daughter who states she is a victim of a non-recent, one-time molestation that occurred sometime between the age of 5-6yrs by a close family friend. My adult daughter agrees that she never disclosed to me exactly what happened because she said she was afraid. She said she only disclosed a little to me at the time because she did not want to ruin the family unit. She also said that when she disclosed it to me, I met her with resistance and said to her, “please tell me exactly what happened because this is something that can ruin the family.” I asked her to pretend I was her and she was the abuser. She placed her hand on my knee and held it. I recall exactly that, and she agrees that is exactly what she told me. I told her if it happened again or something, anything, made her feel uncomfortable, to let me know. She never mentioned anything again. At around age 11, she had a second opportunity to disclose the one-time molestation, as she calls it, to a teacher who was teaching a class on appropriate and inappropriate touching. I had to sign a waiver because they were going to go into detail about their private parts. My daughter at the time said the class was great and the kids were silly but that she felt so comfortable with the teacher that she told her the story that she had told me a couple of years earlier. I asked the teacher if the course had gone well, and she said yes, and that my daughter had the tools necessary to know what was right and wrong. That she would be fine. She told that teacher the same story. Which basically was that the abuser had put a hand on her leg. She said it didn’t sound right but that she did not want to disclose the information because she wasn’t sure.
Recently, she disclosed something entirely different. That the abuser had actually touched her private parts under her panties. I wanted to die. I immediately attended therapy with her, where she disclosed this painful event, and I was devastated for her. Then while describing and talking about herself, she begins to say that she had a hard time understanding if the abuse occurred or not because she had a hard time distinguishing between reality and fantasy. That she always needed someone to validate her stories. Sometimes she would dream things, and they felt so real that she could not tell the difference between dreaming it or it really happening. She even went so far as to say that she had disclosed this information a couple of years back to me in therapy and that I confronted the abuser and forgave him, and believed him over her. Totally INSANE because this never happened. This was all said in therapy, and it is well documented. You can imagine the shock of the therapist and myself. We all stared at each other in disbelief because we knew no such thing had happened. The first time she disclosed this terrible crime was a few days earlier, before the therapy session. And the therapist agreed that she knew of the abuse allegation before me but could not say anything until my adult daughter was ready to disclose it and that until that day, it had never been disclosed in therapy. My daughter just stared at us because she did not believe us. The therapist had to stop the conversation and remind her that at no time had I ever been informed of the abuse or anything else. We were shocked, completely shocked, because she argued the point and then realized that maybe she was wrong. My daughter, God Bless her, was always known as an attention-seeking child. Her father emotionally abused her for 18 years of her life. I did everything humanly possible to empower and protect her, and today she is a recent graduate in the medical field and successful. But she has admitted to being extremely jealous of her half-siblings because they never endured what she endured, emotional abuse and this one-time molestation. So I say to myself, knowing what I know now, do I defend her again, allow her as I have always to believe all the things she has always said to be true even though it was genuinely impossible, or do I say, WAIT this is way too serious to let someone get away with it. Can you imagine her accusing someone of something so serious and them not knowing what I know, which is that she cannot distinguish between reality and fantasy? Is that fair to the alleged abuser, who has absolutely no pattern, history, or anything to indicate that any such behavior has ever existed in his life? I am sad for everyone in this situation. Everyone has a right to know the mental state of an accuser as much as the accuser has a right to voice her betrayal/crime and bring to justice her abuser.