Mathews became the focus of an undercover investigation in August 2017 and was indicted in November for attempting to meet with the intention to engage in sexual activity with a female he believed was a 13-year-old Miami 8th grader.

MIAMI – Thomas Crawfish Mathews, former vice chairman of the Quapaw Tribe of Oklahoma’s Business Committee, pleaded guilty to a felony count of attempted enticement of a minor Tuesday at a Tulsa federal court, according to court documents.

Mathews became the focus of an undercover investigation in August 2017 and was indicted in November for attempting to meet with the intention to engage in sexual activity with a female he believed was a 13-year-old Miami 8th grader.

Mathews resigned from his position serving as vice chairman of the Quapaw Business Committee following the November indictment.

With the official entry of his voluntary plea March 6, Mathews has waived his right to a jury trial and was required to verbally admit in court the facts of the charge against him.

Mathews' statement in the petition to enter a guilty plea approved by U.S. District Judge Claire Eagan reads:

"I, Thomas Crawfish Mathews, age 35, admit that on or about August 31, 2017, in Miami, Oklahoma, in the Northern District of Oklahoma, I engaged in a conversation with a person I believed to be thirteen years of age. I used my cellular phone to communicate with the person using the Whisper app. In the communications, I knowingly discussed unlawful sexual relations with the person and proposed a related in-person meeting which is attempted enticement. I understand that the use of the cellular phone is a facility of interstate commerce."

Sentencing is scheduled for June 6 at 9:30 a.m. in Tulsa where Mathews will face a minimum mandatory sentence term of 10 years in prison. The maximum statutory sentence for the charge is life and a fine not to exceed $250,000, according to court filings.

The plea agreement on record outlines that following any term of incarceration Mathews is also subject to supervised probation for a minimum of five years.

Mathews, who was previously under conditional house arrest with an unsecured bond, was remanded to the custody of U.S. Marshals at the conclusion of his appearance March 6 and was booked into the Okmulgee County Jail the same day.

U.S. Assistant Attorney Jeffrey A. Gallant would not comment on the plea agreement beyond referring the News-Record to the publicly available filed court documents.

Section 13 of the plea agreement titled Further Prosecution reads in its concluding paragraph:

"The United States agrees to forego further prosecution in the above-referenced district (Northern District of Oklahoma) related to/or arising from communications made through the Whisper application by defendant to any minors known by the Government in the form of real and/or application usernames."

Gallant did express high praise for the investigative work performed by local law enforcement in conjunction with Homeland Security in the case.

"I want to commend local law enforcement in Miami for their investigative work with Homeland Security in protecting children and being another example of how hard these professionals work day-in and day-out for their communities," said Gallant. "The Miami community should be very proud. I really want to emphasize it was the vigilance of their local law enforcement, the Miami Police Department, and all they do."

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Initial Investigation

Federal court records unsealed Nov. 14, 2017, revealed Mathews became the focus of an undercover investigation in August and attempted to meet with the intention to engage in sexual activity with a 13-year-old in Miami, Oklahoma.

According to a probable cause affidavit filed in the case, a Miami Police Department (MPD) detective undercover as a 13-year-old female living in Miami under the username “Angel2022" posted “Mission complete lol,” on social app Whisper.

The detective was contacted a short time later by a user known as “Big T,” later identified as Mathews by federal investigators.

Whisper is a free social media mobile app that allows users to post and share photos and video messages anonymously.

During the August online conversation, Mathews went on to ask the undercover detective if he wanted to “hook up,” and made plans to meet the detective who he believed to be a 13-year-old, 8th-grade female.

The following is the transcribed conversation, in part, that took place between the undercover detective (UC) and Mathews:

Mathews: “ohhh so have u had sex?”

UC: “Yea well sorta I guess once. It just didn't last that long.”

Mathews: “Ahhh u need someone to do u good!”

_ _ _

Mathews: “Ok. Where do u wanna meet”

UC: “Somewhere where I can walk to I can't drive lol I'm only 13”

During the conversation, Mathews also asks the UC "can u keep a secret" and later stresses “Gotta keep it a secret.”

On Aug. 31, 2017, Mathews was observed by MPD under surveillance arriving at two separate meeting locations arranged by “Big T” and “Angel2022″ during their Whisper chat.

MPD approached Mathews at the second location where he denied he was in the area to meet with a 13-year-old to engage in sex and allowed an iPhone in his possession to be searched.

His phone was ultimately returned, and Mathews was released from the scene.

Indictment

On Sept. 6, 2017, MPD Detective Aaron Crockett served an Ottawa County search warrant to obtain subscriber information and IP logs for the “Big T” account. The account information enabled detectives to ascertain the time and the unique Whisper ID associated with the account, capture when the account was used and that it had been deleted in close time proximity to the encounter Mathews had with detectives Aug. 31.

Requested records were also obtained from CableOne on Sept. 7 of subscriber information for the IP address utilized by the “Big T” account. On Sept. 20, requested records were also obtained from Verizon of subscriber information for remaining IP addresses utilized by the “Big T” account identified on Aug. 29, 30 and 31.

On Oct. 3 an application for a search warrant was filed in federal court and on Oct. 11 a search and seizure warrant was issued and then executed at Mathews' residence in Miami citing the detectives' background investigation and probable cause as the reason for the request.

An inventory of property seized in the executed search lists marijuana snacks, and four iPhones.

Mathews was arrested and charged in Ottawa County District Court for felony charges of possession of a controlled dangerous substance/marijuana and child neglect because the items were allegedly found in a location accessible to minors in the residence.

On Nov. 2 an application submitted by a Homeland Security Investigations (HSI) special agent was granted and executed to obtain "All digital evidence associated to WID (unique Whisper ID) on the search warrant," for the Whisper account identified as "Big T" by U.S. Magistrate Judge Paul J. Cleary.

Mathews was arrested and arraigned on Nov. 14 in Tulsa in the U.S. District Court for the Northern District of Oklahoma, according to an indictment of the grand jury charge filed on Nov. 6 by Gallant.

Mathews was subsequently released on his own recognizance after a $25,000 bond was set by Magistrate Judge Frank H. McCarthy.

Later Developments

According to an affidavit filed on Dec. 14, a search warrant was requested by HSI agent John W. Perez for the search of a black 2014 Nissan Titan four-door pickup truck with a Quapaw Tribal license plate alleged to be a vehicle driven by Mathews.

The background on the investigation referred to in the affidavit was based on information uncovered by MPD in its ongoing investigation and Mathews' subsequent indictment on one federal charge of attempted enticement of a minor.

In addition, the affidavit states a search granted for Mathews’ Whisper account for chat initiated by him to anyone appearing to be under the age of 18 revealed he allegedly initiated chats with approximately 58 underaged users through Whisper prior to his November indictment.

Several screen names were also linked to Mathews including but not limited to “Big T,” “random name,” “fun runner,” and “wanna buy a duck."

Whisper app users can adjust how far of a distance in miles they wish to reach out to connect with others within the application. Investigators looked at usernames, IP logs, posts and the latitude and longitude of each post.

Gallant confirmed prosecutors became aware through the ongoing investigation of at least three alleged female minor victims, all 16 years-old at the time, that were contacted by Mathews via Whisper prior to his November indictment.

Investigators conducted interviews with the three discovered females and two of the three alleged instances involved requests for nude photos and one involved a subsequent sexual encounter.

Perez states in the affidavit, that in an interview with one of the minors she told the agent Mathews traveled to her high school in a neighboring state and picked her up after school, and that Mathews drove her to a secluded area behind what appeared to be an abandoned house and once there, Mathews had vaginal sex with her in the back seat of his truck.

She told investigators the sex was not forced but was Mathews’ idea.

According to the affidavit, the minor told Perez she knew Mathews lived and worked in Oklahoma and described Mathews to three investigators.

The minor also identified and described the make and color of the vehicle Mathews drove and gave details about the interior of the truck to the detectives.

Judge Jodi F. Jayne granted the warrant request to allow a search of the black Nissan truck for the purposes of gathering evidence, including DNA, and other items.

Detention Request

Citing the initial investigation leading to Mathews' indictment in November and the additional information uncovered during ongoing investigations and through executed warrants, a hearing took place Jan. 11 in Tulsa federal court for a motion for detention filed by prosecutors.

The minutes of the detention hearing lists exhibits entered by the prosecution containing summaries of the interviews conducted by investigators under the Whisper usernames associated with three alleged minor victims.

Among the points argued in the filed response by Mathews' defense team to the motion for detention was that Mathews should remain free on bond based on the facts that he had no prior criminal history, had demonstrated compliance since his November indictment, was willing to adhere to additional conditions, and that his detention would impede his ability to properly, and rightfully, prepare for trial with his defense team in the case which had been determined to be of a complex nature.

The response filed by Mathews' defense further argued that while several usernames had been associated with Mathews' Whisper account ID and IP addresses, that it was not enough to establish that Mathews was, in fact, the person using or transmitting messages via those accounts citing several other cases and the current evidence in Mathews' case.

Mathews' response also noted that conflicting statements had been given by the alleged minor victim claiming to have had sex with Mathews claiming she first denied meeting anyone on the Whisper app, then stated she had met with Mathews and went for a ride, and later said he picked her up from school in his truck and described a sexual encounter.

Serving as a witness for Mathews during the detention hearing was his mother who spoke to the defendant's community ties, her willingness to monitor him while he remained released as she was home full time due to retirement, and an offer to have all internet connections removed from her home where Mathews would reside under house arrest with electronic monitoring.

Judge McCarthy ultimately ruled Mathews was to remain free on an unsecured bond while facing the federal criminal charge.

McCarthy imposed certain rules and conditions including that Mathews was to have no contact with minor children, including his own without advanced permission from probation officers, would be confined to his parents' home and under their custody, could not travel unless permitted by probation officers and to meet with his defense team, no Internet access, and very limited phone access including the surrender of his smartphone.

Guilty Plea

On March 6, Mathews entered a voluntary guilty plea on the federal charge of attempted enticement of a minor waiving his right to a jury trial.

Mathews was remanded to the custody of U.S. Marshals after his appearance Tuesday and booked into the Okmulgee County Jail the same day.

Sentencing has been scheduled for June 6 at 9:30 a.m. in Tulsa.

Dorothy Ballard is the managing news editor of the Miami News-Record. Email her at dballard@miaminewsrecord.com and follow her on Twitter @dm_ballard.

Miami News-Record associate editor Melinda Stotts contributed to this report.