Forty-two years ago on May 4, 1970, members of the Ohio National Guard opened fire on a crowd of unarmed students at Kent State University, firing between 61 and 67 shots over a period of 13 seconds, killing four students and injuring nine others. The shootings at Kent State symbolized the deep divides that existed in America during the Vietnam War era and played a significant role in shaping the way a generation interacted with its government. The iconic images of the events of May 4, 1970 are just as powerful today as they were when news of the shooting sparked nationwide protests.

The only known audio recording of those events was made by Terry Strubbe, who placed a microphone out of his window and recorded 29 minutes of audio. At least two copies of the Strubbe tape were made, with one ending up in Yale University’s Kent State Collection in 1989. In 2010, the Cleveland Plain Dealer engaged forensic audio engineers to examine a copy of the Yale recording made by Alan Canfora, one of the 13 victims of the Kent State shootings. That analysis made a stunning finding: Shots were fired before the National Guard opened fire. That evidence could be significant, because it could connect an FBI paid informant who was on campus that day and who possessed a gun that might have been the one caught by Strubbe’s microphone.

In 2010, as chairman of the Domestic Policy Subcommittee of the House Committee on Oversight and Government Reform, I opened an inquiry into this evidence. I requested that Yale University make another copy of the Strubbe tape to ensure its authenticity, and sent a letter to Attorney General Eric Holder requesting that the Department of Justice undertake a forensic analysis of this authenticated recording. The DOJ obliged my request; and more than a year later, I received a reply. The DOJ concluded that the tape was unintelligible, but that the sounds preceding the fire from the guardsmen were likely to be the sound of Strubbe’s dorm room opening and closing.

Despite the detailed response from the Justice Department, significant questions remain. There was no attempt to reconcile major discrepancies in conclusions among expert analysts. The role of Terry Norman, the FBI informant on campus that day, was not discussed. In order to lay these questions to rest, I wrote to the Justice Department requesting the full analysis used to reach their conclusions.

The Kent State shootings remain a significant event in American history. Nothing less than a full investigation is warranted.