Indiana man sentenced after admitting to poisoning wife's Coke with drugs 'so he could have sex' with his stepdaughter

An Indiana man who admitted to spiking his wife's Coca-Cola with cocaine and other drugs in hopes of killing her was sentenced to four years in prison.

Alfred RufRichmond Police Department

Alfred W. Ruf, 71, pled guilty Monday to aggravated battery posing a risk of death. A charge of conspiracy to commit murder was dismissed as part of a plea deal, court documents state.

Authorities began investigating the case in 2022 after Ruf's wife, Lisa Bishop, told police conducting a welfare check at their Richmond home that she had been hospitalized several times and believed Ruf was trying to kill her, a probable cause affidavit states.

Ruf allegedly came clean to his wife and confessed "because he felt bad," the affidavit says.

She gave officers a pill bottle containing a white powdery substance and told police that Ruf had been putting the powder into her drinks without her knowledge, the filing says. Bishop also gave officers a Coke can she drank out of and cut open. At the bottom of the can was the powdery substance, according to the affidavit.

Bishop was taken to the hospital where she tested positive for cocaine, MDMA, commonly known as molly or ecstasy, and the depressant Benzodiazepine, the affidavit states. She denied using drugs.

Ruf allegedly told detectives that his wife's daughter from a previous relationship would give him a white powdery substance to put in Bishop's drink, according to the affidavit.

"Alfred stated that the substance would then make Lisa go to sleep for approximately thirteen hours or so," it says. "Alfred stated that he would do this to eventually kill Lisa."

The affidavit says that the daughter and her friend "would call him and tell him to give the substance to Lisa." The daughter and friend would then come to the house, give Bishop "more of an unknown substance."

Ruf said he was in a sexual relationship with the daughter and friend, according to the affidavit.

Ruf alleged that the daughter mentioned a life insurance policy Bishop had and instructed him to "get mom out of the picture," the filing states. The daughter's friend allegedly hinted at wanting to marry him "after they took care of Lisa."

Ruf told authorities he had given Bishop the powdery substance about 12 times from the beginning of September 2021 to the end of December 2021. Ruf said he took his wife to the hospital about six times because of reactions she had to the drugs, according to the affidavit.

Bishop told police that she had been suffering from headaches, drowsiness, and feeling light-headed but did not know what was wrong with her, the filing says. During one incident, Bishop said she felt like she was going to pass out and cut open a can of Coke she drank from.

When she saw a powdery substance at the bottom, she confronted Ruf who confessed, according to the filing.

"Alfred kept going back and forth about what his intentions were for giving his wife the substance," the affidavit says. "He would state that he knew it would kill his wife. ... But then Alfred would explain that he would give his wife the substance just to make her pass out so the other two females would come over so he could have sex with them."

Ruf was sentenced to four years in prison followed by five years of probation. NBC News reached out to his attorney for comment.

At the time of Ruf's arrest in 2022, police said they were still investigating two other suspects, Fox59 reported. The daughter and friend have not been arrested or charged.