A Ramsey County deputy who pleaded guilty to beating his K-9 partner after a night of drinking will return to work Wednesday after successfully contesting his termination.

Brett A. Berry, 49, was fired in April after he was caught on surveillance cameras in the parking lot of the Black Bear Casino lifting his K-9 partner, Boone, forcefully by the collar, pushing him to the ground and striking him several times with the leash while attending a training event in Carlton County.

State arbitrator Gil Vernon wrote in an opinion released Monday that Berry's behavior was an "aberration and that he deserves another (but last) chance to resume his career," and that the sheriff's office erred when it fired Berry by not giving enough weight to the mitigating factors. Berry is entitled to reinstatement but without back pay, the opinion states. He also cannot work with canines.

Ramsey County Chief Deputy Jack Serier said at a news conference Tuesday that the sheriff's office took the right action in firing Berry and that he has "complete confidence" in the internal affairs process that led to that decision despite Vernon's ruling.

A "series of circumstances" the night Berry attacked Boone led to his firing on April 12, Serier said.

"The internal affairs process was extremely well done," Serier said. "It's very much a difficult situation, but we also have to do the next right thing, and that's what we've done every step of the way."

Serier said the sheriff's office is bound by law to follow the arbitrator's findings.

Berry was charged in 2015 with one count each of misdemeanor assault of a public safety dog and animal cruelty. He pleaded guilty this past January to the animal cruelty count; the other count was dismissed.

Berry was sentenced to one year of unsupervised probation, which will end in February 2017, covered Boone's veterinary costs and agreed to attend Alcoholics Anonymous, among other conditions.

Berry and Boone attended the U.S. Police Canine Association's regional certification trials in Carlton, Minn. in June 2015. Berry got drunk the night before the event and was asked to leave the casino. He then took Boone for a walk. A surveillance video showed Berry scolding the dog in the casino parking lot and becoming upset.

Video "then shows the individual pick up his dog by the collar and throw it to the ground," according to the Carlton County Sheriff's Office. That's when the dog bolted from Berry and tried to run back into the casino. The dog made it only past the first set of doors, however, and became trapped in the vestibule. Berry caught up to the dog and struck it several times.

Berry was placed on administrative leave shortly after an investigation began, and was then assigned to security duty at Regions Hospital and handled extraditions and warrants before he was fired, the arbitrator's report said.

Vernon said that the sheriff's assessment of the "risk" of Berry returning to work was not reasonable, and that the likelihood of him engaging in future misconduct was low. Additionally, several supervisors deemed Berry as a "viable officer" and would not have reservations if he returned to active duty, Vernon wrote.

"Officer Berry has the support of his fellow officers, and we believe he can still be an asset to his department and to the people of Ramsey County," said Sean Gormley, executive director of Law Enforcement Labor Services, which represented Berry in arbitration.

Berry will return to work Wednesday in the detention division, Serier said, adding that he will be subject to a "review process."

"These kinds of incidents tarnish the badge not just for our agency, but for all law enforcement agencies," Serier said.

Boone was reassigned to another officer and is still active.

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