What do you want to happen? There are no statute of limitations on war crimes or crimes against humanity, so it is possible your reporting could have larger impact than you intended. Regardless, you should really ask the witness what they wants to happen.

The Library of Congress has a Veterans History Project that solicits all veteran stories, and provides different ways to submit them. (LINK) They offer kits to help people interview their veteran subjects (or do self interviews), and are generally a very helpful resource for personal oral history.

Now of course the nature of this project is a little different than you're asking. They don't put you in touch with historians to interview you; you're submitting material to them. And it basically goes into a big collection with all the other stories. An amazing resource for future scholars, but possibly not what you have in mind.

If you want to contact individual historians, I would suggest researching who has written on topics close to what happened in this case. Then see if they have an institutional email address you can write to, or one for their department, and inquire if they're still working on the topic. As a historian, I'll say that generally our reaction when someone wants a conversation on our speciality topic is: "Yes please let's talk for hours!!"

But as nilhaus wrote above, also you should ask yourself what you want out of this. For a historian to write about it? To make this public in the media? To get the courts or the military involved? I'd also ask (because a historian interested in working on this would definitely ask) whether the person has any documentary evidence or supporting testimony to their account.

I just talked to my friend, and they said they'd be willing to talk to a historian. So, that's the route we're going to go.

From the CJA.org website:

“According to the International Criminal Court, “War crimes include grave breaches of the Geneva Conventions and other serious violations of the laws and customs applicable in international armed conflict and in conflicts “not of an international character” listed in the Rome Statute, when they are committed as part of a plan or policy or on a large scale. These prohibited acts include:

murder; mutilation, cruel treatment and torture; taking of hostages; intentionally directing attacks against the civilian population; intentionally directing attacks against buildings dedicated to religion, education, art, science or charitable purposes, historical monuments or hospitals; pillaging; rape, sexual slavery, forced pregnancy or any other form of sexual violence; conscripting or enlisting children under the age of 15 years into armed forces or groups or using them to participate actively in hostilities.”

If the person was witness to an act that fits these descriptions and the act is unreported; The witness should feel compelled to bring these injustices to light no matter the perceived pain or discomfort to the person or people responsible for the acts. This compulsion should trump all other acts. Justice must be served, especially in instances where the victim can no longer speak on their own behalf.

That being said, it is implied in the field that a historian’s responsibility is to verify, document, and make public their findings on such events. We learn nothing by hiding an evil deed to protect the few. We must shed light on the event in the hopes that it is not repeated.

I’m currently a history student here at a California State University. You could actually record it yourself, and submit it to the Library of Congress or contact a university library with your recording. As a history student it is our job to curate the recordings that are done this way, so your interview could be potentially curated and published on a database!!