OKLAHOMA CITY — A former Oklahoma City police officer convicted of sexually assaulting women while on duty is appealing his conviction and 263-year prison sentence.

Online Court of Criminal Appeals records indicate attorneys for 30-year-old Daniel Holtzclaw, a former Enid resident, formally filed his appeal Wednesday.

Among other things, attorneys allege the evidence at Holtclaw’s 2015 trial was insufficient to convict him of the charges and that he didn’t receive a fair trial because of a “circus atmosphere” during the highly publicized case.

Holtzclaw also claims his attorneys were ineffective during his trial.

In the court document, Holtzclaw’s attorneys say “… his trial counsel was ineffective for failing to investigate and use extant, relevant evidence, by way of his own expert witness, which would have called attention to misstatements of fact by the State’s own expert witness, as well as bolstered an alternate, and innocent, explanation for the presence of one alleged victim’s DNA on Mr. Holtzclaw’s uniform trousers, thereby preventing important information from reaching Mr. Holtzclaw’s jury.”

DNA from one victim was found on the inside and outside of the zipper area of Holtzclaw’s uniform trousers, as well as DNA from other individuals, including from one male, according to the court document.

“According to Oklahoma City Police chemist Elaine Taylor … DNA could have gotten on Officer Holtzclaw’s uniform by way of ‘secondary transfer’ after searching her purse,” according to the document filed by Holtzclaw’s attorneys. “However, this innocent explanation of the presence of … DNA on Officer Holtzclaw’s pants was undermined when she agreed with the prosecutor that it was more likely to have gotten there by way of a liquid medium, such as vaginal fluid, rather than through a transfer of just skin cells through touching.”

The appeal takes Holtzclaw’s trial attorneys to task for not challenging Taylor’s testimony.

“Officer Holtzclaw’s lawyers did not present an expert of their own to contradict any of her testimony,” the appeal states. “Neither did they utilize the powerful tool of cross examination accompanied by her own reports to call into question some of her conclusions.”

Holtzclaw was convicted in December 2015 on 18 of the 36 counts against him, including four first-degree rape counts as well as forcible oral sodomy, sexual battery, procuring lewd exhibition and second-degree rape. He was acquitted on the other 18 counts. He was sentenced in January 2016 to 263 years in prison.

He was accused of raping and sexually victimizing women while on his beat in a low-income Oklahoma City neighborhood.

Prosecutors said Holtzclaw targeted black women in neighborhoods east and north of the state Capitol building. During his month-long trial, 13 women testified against him, and several said Holtzclaw stopped them, checked them for outstanding warrants or drug paraphernalia, and then forced himself on them.

All of the accusers were black. Holtzclaw is half-white, half-Japanese, and the son of a longtime Enid police officer.

Holtzclaw’s victims included a teenager and woman in her 50s. The older woman’s complaint in June 2014 launched the investigation into Holtzclaw.

Holtzclaw’s attorney, meanwhile, described the former college football player as a model officer whose attempts to help the drug addicts and prostitutes he came in contact with were distorted. His trial attorney, Scott Adams, also attacked the credibility of some of the women, who had arrest records and histories of drug abuse, noting many didn’t come forward until police already had identified them as possible victims after launching their investigation.

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