DETROIT -

Frank Murphy Hall of Justice is a place for serious business, and watching everyone’s every move is a serious K-9, who seriously loves treats.

"Hey Abby, it’s not play time it’s work time," said Deputy Jason Matthews of the Wayne County Sheriff’s Department.

Deputy Matthews and Abby, his German shepard, have been a team for the Wayne County Sheriff’s Department since 2009.

"As soon as we turn the corner and we arrive at work, her tail is wagging and she’s happy," Deputy Matthews said.

These days they make up the security duo that greets the jurors, attorneys and just about anyone else who wants to say hello.

"She’s kind of like the mascot of Frank Murphy," Deputy Matthews said.

Slideshow: K-9 Abby works with Deputy Jason Matthews

But big events are their thing. From guarding the field at Comerica Park, to Red Wings games at the Joe, to the Detroit Fireworks, Abby has been by Jason’s side through it all. That was before the five-year-old pup's spunk started to fade.

"She just wasn’t herself," Matthews said. "She lost her appetite, wanted to lay around and didn’t have her passion for life, she just wasn’t excited."

And while Jason caught on to those signs, the vet gave him news he never saw coming.

"At the time the doctor told me she had kidney failure and heart disease and that I should just focus on making her comfortable because she didn’t have much time," Matthews said. "I was in denial. I just wasn’t willing to accept it."

Seeking a second opinion, Abby went to Michigan Vet Specialties.

"She was there for a week and they went through aggressive testing and medication and they put her on a special diet," Matthews said. "Every day I left work not knowing what to expect, I would just go sit with her at the hospital every day hoping for the best."

Abby spent a week in recovery at home. A month ago, Abby returned to Frank Murphy, a thinner yet happier version. But these days working big events takes a back seat to eight rotating medications and a new set of deputy duties for Jason.

"She is on a very limited diet and every other day I have to give her 500 mg of fluids," Matthews said. "Having a K-9 as a deputy is always more responsibility and while Abby requires more attention, I wouldn’t trade her for the world."

Due to Abby’s illness, she can never be a full-service K-9. She is now considered a single-purpose explosive detector and will only assist with security and bombs from now on.

Matthews also has another K-9 named Nags. Abby and Nags rotate their position at Frank Murphy.