A former Louisiana state trooper who had faced felony charges in the 2019 death of a Black man who was beaten while in police custody pleaded no contest to significantly reduced charges on Monday, allowing him to avoid jail time in a case that drew protests and spurred a federal civil rights investigation.

The trooper, Kory York, 51, had initially faced charges of negligent homicide and 10 counts of malfeasance in office in the death of Ronald Greene, 49, who was beaten while in custody after a high-speed chase on May 10, 2019. In an agreement with prosecutors, Mr. York on Monday pleaded no contest to eight counts of misdemeanor battery in exchange for one year of probation, his lawyer, Mike Small said.

The no-contest plea, Mr. Small said, is not an admission of guilt.

Four other law enforcement officers were also charged in the case, but Mr. York, who retired in August, had faced the most serious charges.

“This was an outstanding result,” Mr. Small said.

Family members of Mr. Greene gathered in a courtroom on Monday in Farmerville, La., as Mr. York’s trial was about to begin. Mr. Small said that Mr. Greene’s mother, Mona Hardin, and another family member spoke in court, asking the judge to not approve the no-contest plea agreement.