A lawsuit that put federal agents on trial in the Southern District of Florida for alleged excessive force resulted in a curious verdict, awarding a plaintiff no compensation but hitting four federal agents with $16,000 in punitive damages.

That was a message to law enforcement, according to plaintiffs lawyer Jason Sherry of Sherry Law Office in Miami, even though the verdict didn't survive the scrutiny of U.S. District Judge Paul C. Huck.

"I think the jury thought there was a culture of covering up here," Sherry said.

Sherry's client, prison inmate Reginald Grimes, was arrested on  Jan. 14, 2015, as part of a Drug Enforcement Administration arrest roundup of suspected drug offenders. But much of the day's events are shrouded in mystery because there's no video footage, and almost all eight defendant DEA agents denied being involved in arresting Grimes.

Grimes alleged his arresting officers hit and kicked him after a high-speed car chase in Riviera Beach, while he laid on the ground with his face down and arms outstretched. He was later convicted of conspiracy to distribute heroin, and sentenced to 14 years in prison.

The plaintiff's story was backed up by one witness, U.S. Marshal James Hart, who testified that Grimes did comply with arresting officers after the car chase, according to Sherry.

But the defendants disputed that version of events and denied any wrongdoing. And one week before trial, two marshals came forward alleging they arrested Grimes and that he did resist. But no video, documents or witnesses put them on the scene that morning, according to the plaintiff's team, who say one agent testified that he'd never seen an officer use excessive force in his 23-year career.

Defense attorney Karin Wherry of the U.S. State Attorney's Office in Miami did not immediately respond to a request for comment.

"They, [the jury] like us, will never know what happened, but they found it unacceptable that in five years the defendants could not explain Mr Grimes' injuries," Sherry said.

But Grimes's injuries were minor—or de minimis, as Huck wrote in his ruling, which found the evidence didn't support an excessive-force violation under the Fourth Amendment. It also noted medical staff diagnosed Grimes with a head contusion and gave him only ibuprofen pills, and that he had a criminal history and was known to be dangerous.

Sherry disagrees, and says any ruling that sets aside a jury's verdict deserves scrutiny from the U.S. Court of Appeal for the Eleventh Circuit.

"It doesn't matter whether Mr. Grimes was severely injured, or moderately injured or mildly injured after the handcuffs were placed on him," Sherry said. "The fact that he had any injuries is itself significant because he was restrained at that point, and even a de minimis injury at that stage is a problem."

Jurors do have the option of awarding $1 in compensation when they find a constitutional violation has occurred, but it's unclear why they didn't in this case.

They found defendant agents Richard Rott, Steven Hearn, Andrew Tallichet and Anton Franks had acted with malice and reckless indifference but found the plaintiff hadn't proved any wrongdoing by four others.

Jeffrey Goldberg and Gil Ben-Ezra of Hughes Hubbard & Reed in Miami were also part of the plaintiff's trial team.

"Although we're disappointed with the judge's decision," Goldberg said, "we appreciate the time and attention the court gave this matter, and are grateful that the jury took (its) duty so seriously in rendering (the) verdict."

Read more: