Former Sarasota Sheriff’s Deputy Frankie Bybee volunteered to watch a 79-year-old woman’s dog while she was in the hospital. Investigators say it was part of a scheme to steal thousands. (Courtesy of Sarasota Sheriff’s Office)

To outsiders, Sheriff Deputy Frankie Bybee was doing exactly what his sheriff demanded of employees — going beyond the call of duty to look out for a resident of Sarasota, Fla., a county full of retirees.

The 79-year-old that Bybee had befriended lived alone and struggled with chronic illness, so for months, Bybee appeared at her house just to check up on her.

He introduced her to his children. She introduced him to her two-year-old Yorkshire terrier, JJ.

But Bybee’s intent was more insidious, the Sarasota Sheriff’s Office claims.

In the end, he would be accused of trying to steal tens of thousands of dollars from the woman — using JJ as leverage to insert himself into her life.

When the scam unraveled, investigators say, the sheriff’s deputy broke into the woman’s house, pinned her to a chair, then stuffed sleeping pills down her throat to try to make a murder look like suicide.

“He used his uniform — our uniform — to win her trust,” Sheriff Tom Knight told The Washington Post on Tuesday, a day after escorting the 18-year veteran to jail in handcuffs.

The relationship started in October, when Bybee was dispatched to the woman’s home for a call. The woman, originally from Oklahoma, was “in poor health (and) was in need of services,” according to a probable cause affidavit filed Sunday. Bybee drove her to Sarasota Memorial Hospital. Before he left that day, he prayed with her.

They struck up a friendship, in part because the woman was inclined to trust a uniformed deputy, Knight told The Post.

Sometimes, Bybee showed up in plainclothes, sometimes in uniform.

To outsiders, Bybee, 46, looked like a good officer. “I preach to them, we’re here to serve, not just to police,” Knight said. “We want them to have a balance between protecting the community, but also have a social side to them. We expect them to help residents when they can.”

As time passed, the relations “became more familial,” according to the affidavit. Bybee inquired about the woman’s long-term health-care plans and her financial accounts.

During one visit, Bybee learned, she was going to be hospitalized again. She wanted someone she trusted to look after JJ.

Bybee said he could do it. All he asked for was a check for $1,000, in case the dog needed grooming or they had to make an emergency trip to the vet, Knight said.

In the hospital recovering, she received a photo in a text message from Bybee. He’s lying on a bed. Next to him JJ also stared into the phone.

Around that time, Bybee’s behavior began to change. He had inserted himself “into her personal life and personal affairs,” the affidavit says. And he “had become controlling.”

He had “re-homed” JJ to someone he’d found on Craigslist, the affidavit said. Bybee “did not return the dog to the victim and at this time [Sunday] the whereabouts of the dog are unknown.” Investigators say he had also swiped a few of the victim’s checkbooks and had her financial information.

A few days before Christmas, she called the Sarasota Sheriff’s Office. She wanted help pushing Bybee out of her life. And she wanted her dog back.

Knight says his department launched an internal investigation of Bybee, who had been disciplined before for dishonesty.

As they were drilling into the details, an envelope with Bybee’s name on it showed up in the mail at the sheriff’s office on Jan. 9.

Inside was a $50,000 check made out to Bybee and a check for each of his three children for $5,000 apiece. The woman told investigators she didn’t write them. They weren’t in her handwriting, she said, and she never used her middle name when she signed for things.

The investigation intensified. Bybee was placed on leave. The allegations, if true, would end his law enforcement career and land him in jail.

That’s when investigators said they believe that Bybee tried to cover his tracks and silence the primary witness in his case.

Three days after the checks showed up at the sheriff’s office headquarters, the woman was sitting in her living room when she heard someone come through the unlocked front door.

It was Bybee, she later told investigators. He was wearing dark clothes and had on blue latex gloves. He “was agitated and angry with her because her complaint against him led him to be placed on administrative leave from the Sarasota county Sheriff’s Office,” court documents say.

He grabbed her face with his gloved hand, making her bleed, the documents say. He put his knee in her pelvic area, pinning her to the chair, and tried to force a pill in her mouth — prescription medication that she used to fall asleep.

She fought back, but lost consciousness.

When she woke up, Bybee was gone, and her home was warm. She staggered into the kitchen, “which was very hot,” the documents say. That’s when she noticed the door to the garage was open, and her Toyota Camry was running.

“The roll down garage door was closed and the garage and residence had filled with carbon monoxide,” the affidavit says.

The woman survived, and called police. Bybee was arrested Monday and charged with attempted murder, exploitation of the elderly, grand theft, burglary and battery. He made his first appearance Monday morning, and his bail was set at more than $1 million. It was unclear whether he had obtained an attorney.

Now, investigators are poring over Bybee’s nearly two-decade-long career.

“This is still an open, fluid investigation. I think it’s important that since he’s worked here for 18 years, we would encourage anyone in the public that has maybe had contact with him — to contact the criminal investigations section,” Knight said.

Knight said Bybee wouldn’t say anything to interrogators, but they had obtained warrants for his electronic devices and were looking into his bank records.

And Bybee still wouldn’t reveal the location of JJ, but investigators did.

The dog was united with her owner on Monday.

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