‘Predatory behavior’: Guilty of sex crimes, Boise man to be in prison for life
A Boise man will spend the rest of his life in prison after he was convicted in two separate cases involving the assault and sexual abuse of minors — with one of the incidents taking place in a Boise State University dorm room.
Isaiah Williams, 22, was arrested in November 2024 on suspicion of rape, forcible penetration and possession of a controlled substance. The Boise Police Department sought the public’s help because they believed there could be more victims. More women came forward and the then-20-year-old was charged with 14 offenses involving several victims.
Seven of those were sexual assault charges, according to court records. The other charges involved aggravated assault and drugs. Four trials later, Williams was found guilty of 12 offenses, including sexual assault, aggravated assault and lewd conduct with a minor.
On Tuesday morning in a joint sentencing for two cases against Williams, 4th District Judge Cynthia Yee-Wallace sentenced him to life in prison with no possibility of parole.
In one of the cases, dating to 2022, Williams was convicted of lewd conduct with a child under 16 and sexually abusing a minor under 16. In the other case, from 2024, he was convicted of aggravated assault, destruction of evidence, witness intimidation and intentional destruction of a telecommunication line.
“You are the type of person that every parent fears when they send their children off to college,” Yee-Wallace told Williams during the sentencing. “Very few people who come before me truly engage in predatory behavior, and you are one of them.”
During Williams’ sentencing, Ada County Prosecutor Jan Bennetts said that in 2022, Williams sexually abused a 15-year-old girl in his BSU dorm room, provided her with alcohol and isolated her in his bedroom. She said that when a friend attempted to intervene, Williams physically removed her from the room and locked the door.
In 2024, Williams strangled a 17-year-old girl inside his apartment and took her phone to prevent her from calling police, Bennetts said. The prosecutor said Williams told the girl that “even if she reported the assault, no one would believe her.”
Video evidence from Williams’ phone confirmed the strangulation, Bennets added, and she said in court that Williams’ behavior was “predatory and deliberate.”
“He chose his victims carefully — a child and a young woman who were targeted, assaulted, and told no one would believe them,” Bennetts said. “The jury believed them. ... This sentence reflects that and the seriousness of his conduct.”
Williams still awaits sentencing in the original case that saw his first arrest. On Nov. 19, 2024, Boise police received a report from the victim that a man raped her at his apartment. Shortly after, BPD arrested Williams, who was accused of rape, forcible penetration using a foreign object and possession of marijuana.
Court records showed that a grand jury indicted Williams on the original three charges — plus five more the Ada County Prosecutor’s Office tacked on after other people came forward.
The indictment listed two counts of rape, two counts of forcible penetration using a foreign object, sexual battery, possession of marijuana, delivery of marijuana and possession of drug paraphernalia. According to the document, the sexual assault charges involved three women in October and November 2024.
On Nov. 19, 2024, Boise police received a report from the victim that a man raped her at his apartment. Shortly after, BPD arrested Williams, who was accused of rape, forcible penetration using a foreign object and possession of marijuana.
Court documents show that in March 2025, a grand jury indicted Williams on the original three charges — plus five more the Ada County Prosecutor’s Office tacked on after other people came forward against Williams.
The indictment listed two counts of rape, two counts of forcible penetration using a foreign object, sexual battery, possession of marijuana, delivery of marijuana and possession of drug paraphernalia.
According to the document, the sexual assault charges involved three women with incidents that happened in October and November of 2024.
Williams was found guilty on all charges except one of the rape counts, in which the jury could not come to a unanimous decision. The sexual battery charge had been dismissed by the court.
Williams will be sentenced on June 5 for those crimes.
Here is a full list of the charges for which Williams was convicted:
Felonies
- Rape
- Forcible penetration by use of a foreign object (two counts)
- Lewd conduct with a minor under 16
- Sexual abuse of a minor under 16
- Possession of a controlled substance with intent to deliver
- Delivery of a controlled substance
- Aggravated assault
- Destruction, alteration or concealment of evidence
- Intimidating, threatening or harassing a witness from testifying
Misdemeanors
- Possession of drug paraphernalia with intent to use
- Intentional destruction of a telecommunication line or instrument
