WASHINGTON – When District of Columbia police began outfitting some officers’ shirts and glasses with miniature cameras in the fall, the objectives were obvious: to protect residents from overly zealous officers during arrests as well as to protect officers from any unfounded complaints.

But this month in D.C. Superior Court, prosecutors and defense attorneys explored another benefit of the video: as evidence for trial.

The case, one of the first in the Washington region to use police body camera footage in court, involved a common assault allegation. A District man accused his onetime roommate of beating him on an August afternoon in 2013 after an argument over missing belongings.

When Michael Fouse of Southeast Washington took the stand Jan. 8, he testified that Allen Wells, his former roommate, had come to his apartment with four other men one summer day. Fouse said two of the men held him down as Wells punched him in the face and head “about 25 to 30 times” and then kicked him in his chest.

But in a video that Wells’s attorney, Stephanie Johnson, played in court – taken from a camera worn by one of the police officers who arrived just minutes after the altercation – Fouse, 54, never mentioned those details. He told the officers only that he was “assaulted” and that “everything happened so quickly, I don’t remember.”

Wells and his attorney cited the video as they argued that there was no brutal attack and that Wells, 67, acted in self-defense after Fouse pushed him. Prosecutors used the same video to point out the victim’s bloodied face and T-shirt.

Ultimately, Judge Fern Saddler found Wells guilty of simple assault.

Such evidence is likely to be increasingly considered by judges and juries across the country. Last month, President Barack Obama asked Congress for $75 million to buy 50,000 body cameras. The proposal came after Michael Brown, an unarmed teenager in Ferguson, Missouri, was fatally shot by a police officer.

Around the Washington area, District police have launched a pilot program to test the cameras, and officers in Laurel, Maryland, have been using them since the spring of 2013. Prince George’s County police in Maryland said they are planning to introduce the cameras, pending approval of the County Council.

The video is far from polished, offering a choppy view from one officer’s vantage point with audio that can be difficult to hear. Still, the cameras can provide a snapshot of the chaotic moments after a crime or during a confrontation with police, capturing the statements and emotions of those involved. Such video can help bolster – or contradict – testimony from officers, victims or witnesses.

Michael White, a professor at Arizona State University’s School of Criminology, wrote a report for the Justice Department last year about the legal benefits derived from video footage. White said that in the United Kingdom, where officers have been using body cameras since 2005, court officials have seen an increase in guilty pleas as a result.

“The great thing about the technology is that it provides a permanent video record of what happened. If there is a ‘he said, she said’ aspect such as in assault cases, the defense and the prosecution can see what transpired, the behavior of the suspect and victim, and whether police followed protocol at the time of the arrest,” White said.

In the District, U.S. Attorney Ronald Machen Jr. said prosecutors are “optimistic” about the use of body camera video in the courtroom and called the information “valuable.” But he said that there are some concerns about the collection and retention of the videos and that he hopes District officials commit resources to storing the videos long term, especially for cases that take a year or longer to bring to court.

“Our biggest concern with respect to this issue is that in order for body cameras to work effectively in the courtroom, it will be imperative for the city to devote significant resources to effectively preserve, process and produce the extraordinary volume of recordings generated by the cameras so that the government can uphold its obligations to provide these materials to criminal defendants,” Machen said.

A handful of courts nationwide have begun using the body camera footage as evidence. Last summer, such video was played for a jury during a Butte, Montana, murder trial in which the first officer on the scene, who had a camera attached to his vest, was able to ask a dying man questions about his assailant.

In Vermont, prosecutors have cited body camera video in the case of a man accused of attacking his wife with a baseball bat.

In the D.C. case, the responding officer, Todd Korson of the 7th Police District, had been one of the first officers to use the body cameras. Korson testified that he had begun wearing the camera about a year earlier, after a shooting incident, but did not provide details.

The video shows officers questioning Fouse and Wells just moments after their altercation at the Green Street apartment in Southeast.

During the two-day misdemeanor trial, both the prosecution and defense highlighted portions of the video for the judge.

Assistant U.S. Attorney Rosamond Xiang played the video in court, noting the moment when Wells told the officer that he struck Fouse because he was “provoked.”

On the video, Wells says: “We were arguing, and he pushed me when he walked by me. I hit him with my hand. When he pushed me, I reacted.”

Johnson, the defense attorney, tried to cast doubt on Fouse’s account by using the video to point out even minor inconsistencies in the statements he had given. Fouse testified that he was not drinking before the altercation. But Johnson pointed out a section of the video showing him telling paramedics that he had drunk “a couple of beers.”

She stressed that Fouse’s first description of the incident was vague and questioned his later recollection of a lengthy attack.

Fouse testified that he was “dazed and confused” in the minutes after the beating. As a result, he told the judge, he did not remember what he told the officers or paramedics at the time.

During questioning by the prosecutor, Korson said he was not surprised that Fouse was reluctant to provide extensive details just minutes after he and his partner arrived on the scene. The officer, who has been on the force 15 years, testified that it was not unusual for victims to be in shock or embarrassed about giving full details right after a violent incident.

Finally, the defense used the video to show that even police officers investigating a case can have less-than-accurate memories. Johnson used the video to question Korson’s recollection of moments after he responded to the assault call. She asked the officer twice whether he had taken photos at the scene. Each time, he said he had not.

Johnson then played the video, which showed Korson snapping photos. The officer conceded. “I definitely took a picture, but I don’t remember taking a picture,” he said.

Johnson filed an appeal of the conviction last week.

Washington Post staff writers Lynh Bui and Magda Jean-Louis contributed to this report.