The sentence comes just over a month after a sobbing Holtzclaw was convicted on 18 of 36 counts, including four counts of first-degree rape and four counts of forced oral sodomy.
Prosecutors said Holtzclaw selected victims in one of Oklahoma City's poorest neighborhoods based on their criminal histories, assuming their drug or prostitution records would undermine any claims they might make against him.
Then, he would subject them to assaults that escalated from groping to oral sodomy and rape, according to the testimony of 13 victims. Holtzclaw, whose father is a police lieutenant on another force, waived his right to testify.
Two of those women shared their stories with CNN on Wednesday, recounting horrific memories of being forced to perform sexual acts by a serial rapist with a badge who was supposed to protect and serve.
Jury wants 263 years
Because the victims are black, race has been regularly invoked in the case. His trial began in November and was criticized by activists after an all-white jury was chosen. Protesters repeatedly gathered outside.
Holtzclaw, whose father is white and mother is Japanese, is identified as "Asian or Pacific Islander" by court records
Attorney Benjamin Crump, who represented the families of Trayvon Martin and Michael Brown, has criticized the media, asking, "Where is the national outcry for their justice?"
Crump praised the sentence Thursday saying it was "a landmark victory."
"All the women were victims, from the 17-year old teenager to the 57-year old grandmother. This is a statement for 400 years of racism, oppression and sexual assault of black women; a statement of victory not only for the 'OKC 13,' but for so many unknown women," Crump said in a statement.
On Wednesday, Holtzclaw's lawyers asked for a new trial, alleging prosecutors did not disclose newly discovered evidence -- including DNA evidence and the accounts of accusers who falsely claimed to be victims -- to the defense, according to CNN affiliate KFOR
. Court documents posted on the station's website
say a detective referenced the evidence in a Facebook post.
The judge denied the motion for a new trial.
The defense team filed for an appeal in court on Thursday, and it was denied, Crump said. They plan to appeal again, he said, but he was not sure what arguments they will use.
Holtzclaw's attorneys aren't the only ones declaring his innocence, despite the verdict. His sister also runs a blog dedicated to telling her brother's "untold story."
One of Holtzclaw's victims, Jannie Ligons, grandmother of 12, was among those who spoke at the sentencing on Thursday.
In an interview with CNN this week, she recalled driving down Lincoln Street when Holtzclaw pulled her over and told her she was swerving, "which was untrue," she said. He told her to get out of the car.
"He put a flashlight on my chest. He told me to pull my pants down to my knees. I did that but real quick and pulled them back up again. He pulled out his flashlight and shined it on my privates. I said. 'Sir, you not supposed to do this.' He said, 'Get back into my vehicle.' I did what he said. I began to get very, very scared," Ligons said.
She remembers him telling her, "Damn, you got a big ass."
"I thought he was going to kill me because I had seen his face and could tell on him and he was an officer and had to know he wasn't supposed to do this," she said.
That's when Holtzclaw ordered her to perform oral sex, she said. Her mind racing and tears gushing from her then-57-year-old eyes, she was both disgusted and terrified.
"I tried to perform oral sex," she said. "And trying to talk, I kept saying, 'Sir, please don't make me do this.' I said, 'Are you gonna shoot me?' He said, 'I promise I am not. ' I didn't believe him. I kept seeing his gun while he was making me do this right there on the street. I was sitting in the passenger side of the car and he was standing there. It was so horrifying. It was unreal. I cried and cried," Ligons said.
Finally, he let her go, and "I decided right then If he didn't kill me I was going to tell on him," she said.
Rape in a hospital bed
She picked up her daughter and went to the police station. Investigators interviewed her and sent her to the hospital. She soon learned she was the last in a string of sexual assaults and rapes committed by Holtzclaw.
"The detective I talked to in the hospital came in and she believed me. While she was writing the report she said, 'I got a good idea who it was,' " Ligons said. "I was relieved at first, but then I wondered why he was still on the street if they knew who it was."
Ligons told reporters after the verdict was announced last month that she had to enter therapy and later "had a stroke behind this."
Another victim, 24-year-old Shandegreon "Sade" Hill, told CNN she was intoxicated the night Holtzclaw arrested her.
He promised to get her prior charges dropped, but while she was handcuffed to the hospital bed trying to detox, he raped her, she said.
"He started to touch me. He touched my breast. From there, I just didn't know what to think. I am in his custody because whatever he tells me in my mind I just did it. As far as I know I could wind up dead in the hospital saying I was overdosed," Hill said.
"He violated me. And made me give him oral. He stuck his hands into my privates. He done everything against my will, " she told CNN, her voice shaking and angry.
Holtzclaw continued to pursue her, even following her to her home and stalking her on social media, she said.
These are just two of the stories from the 13 victims, one of whom was 17 at the time and testified she was raped on her mother's front porch.
Grandmother brought him down
Ligons' report would be the one that finally yielded Holtzclaw's arrest. After she went to police and media outlets, investigators found another dozen victims. She now has a civil lawsuit pending against the former officer and the city, filed on behalf of several victims. Hill has filed a state civil lawsuit
against Holtzclaw and Oklahoma City.
Crump has called Ligons "a true hero -- not just for black women but all women."
"The statistics on rape victims reporting the crimes against them are low to being with. This grandmother had the strength to come forward not just against her assailant but against a police officer. That is a frightening thing to do," he said.
Holtzclaw was a former linebacker on the Eastern Michigan University football team
and graduated with a degree in criminal justice.
Prosecutors say his ruthless scheme began during a June 2014 traffic stop. He was fired
from the force in January 2015 after an internal investigation.
"Your offenses committed against women in our community constitute the greatest abuse of police authority I have witnessed in my 37 years as a member of this agency," Oklahoma City Police Chief Bill Citty wrote in the termination letter, according to CNN affiliate KFOR