Weeks of sexting and nonstop phone calls weren’t enough to score.

So one Missouri deputy allegedly began blackmailing his prey, telling a married woman she could spare her husband certain arrest by sleeping with him.

According to a federal civil rights violation case filed this week, the lascivious lawman then plied the woman with a spiked soft drink and forced her to stare down the barrel of his loaded service pistol resting on a cheap motel nightstand while he got on with the raping.

If only Jane Doe knew who she was dealing with.

Even before he donned the badge, Rainey was known to use his sweet talk to charm women, said a source close to his family who requested anonymity. “He’s good at reading people and he can kind of tell when somebody is vulnerable or stressed.”

“He plays off that,” the source added.

It seemed to start off innocently enough.

Deputy Rainey was on duty with the Gasconade County Sheriff’s Office on July 14, 2012. He was dispatched to check out a call about a temporary restraining order filed by a young woman against her estranged husband, according to the federal civil complaint filed on her behalf on Monday in St. Louis’s Eastern District Court. Upon arrival, Rainey laid eyes on his potential conquest and “obtained her address and telephone contact information,” the papers say.

Rainey allegedly fired off 1,288 text messages and rang Jane Doe 87 times, according to the complaint.

Many of those texts are described as “sexually explicit in nature.”

And before the motel rendezvous, Rainey attempted to force a kiss on the married woman while “standing in the doorway” of her home, according to the complaint.

Despite her rebuffs, the armed and uniformed Rainey told Doe that he was going to arrest her husband based on a “fictitious warrant.” There was an investigation “Rainey was supposedly undertaking,” the civil complaint says.

But the charges were ginned up, apparently a means to bed Doe, who was reportedly 17 years old at the time.

He allegedly told Doe he could “make this all go away” if she would sleep with him, the civil complaint says.

And on August 4, 2012, while Rainey was on duty, he arranged to detour to Doe’s house, picked her up, and checked into an Owensville, Mo., motel using a “fictitious name,” the papers say.

Inside the room, the woman was made to drink from “an opened can of soda,” after which she says she began to feel “drugged.”

Doe was down for the count and according to the civil complaint Rainey then unholstered his pistol and “placed it on the nightstand next to the bed, with the barrel of the firearm pointing towards where [Jane Doe] was lying.”

With the firepower and authority all at play, Rainey then began “having nonconsensual sexual intercourse with [Doe],” the papers say, as she lay there at gunpoint.

The civil complaint accuses Rainey of forcible rape while on the clock and a former Gasconade County deputy sheriff, Randy Esphorst, and the county of failing to properly supervise him. The new complaint comes after Rainey, 51, and his 46-year-old pal Jonathan Pohlmann—who had allegedly slept with the young woman on previous occasions—were both slapped with state charges in late June.

Those charges include corruption by a public servant for Rainey and multiple counts of sexual assault, statutory rape, and “use of child in a sexual performance,” stemming from alleged incidents in January, February, July, and August 2012 involving at least two underage women.

Rainey, who resigned from the sheriff’s department in November 2012, is free on $50,000 bond.

Now a civilian, Rainey is trying to contest criminal charges brought against him after a yearlong investigation that ended in November 2013 accusing the father of two of using his Gasconade County Sheriff’s badge to drug and forcibly bed Jane Doe.

With the civil suit Doe is seeking more than $75,000 for allegedly violating her.

The 51-year-old hadn’t been deputized for very long, according to a source close his family.

Before he was playing sheriff, Rainey sold cars and also souped them up with bass-heavy stereo systems.

The divorcé had apparently long had a randy rep. “He doesn’t think between his ears—he follows his other brain between his legs,” a source said.

Facing the rape charges, Rainey has since sought to water down the allegations in his recounting to his family, the source said. He painted his encounter with Doe not as a crime but consensual. “He’s told them some details but he’s claiming innocence…that there was no force involved,” the source said.