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Press Release


For Immediate Release
U.S. Attorney's Office, District of Wyoming

Dr. John R. Sink, Jr., who is a Ph.D. psychologist, and his wife Diane M. Sink pled guilty on September 25, 2018 before Federal District Court Judge Alan B. Johnson in federal court in Cheyenne to making false statements to Wyoming Medicaid as part of a scheme to fraudulently bill Medicaid for alleged mental health services. U.S. Attorney for the District of Wyoming Mark A. Klaassen, whose office prosecuted the case, announced the guilty pleas.

According to court documents, the Sinks operated a psychological practice in Cheyenne, Wyoming. Between February 2012 and December 2016, the Sinks submitted to Wyoming Medicaid over $6.2 million in bills for alleged group therapy, which consisted of activities that did not qualify as group therapy under Medicaid rules. The Sinks knew their bills contained material false statements because the services provided by the Sinks did not qualify as group therapy, the hours billed did not accurately report the time each Medicaid beneficiary was actively participating in any activities, and the Sinks were not using up-to-date treatment plans to guide each Medicaid beneficiaries treatment as required by Wyoming Medicaid. The Sinks also submitted falsely backdated treatment plans to Wyoming Medicaid when the program audited the Sinks’ business in May 2016. The Sinks made these false statements knowing that Wyoming Medicaid would not pay for the alleged group therapy if the program knew the true nature of the services being provided by the Sinks, and to conceal their fraudulent billing scheme.

"Health care fraud is a serious crime that harms all of us through higher taxes and insurance premiums. The Sinks’ guilty pleas show that the United States government will investigate, prosecute, and punish the criminals who attempt to defraud our health care system," said U.S. Attorney Mark A. Klaassen.

"Today’s guilty pleas send a strong message to anyone considering engaging in health care fraud," said Federal Bureau of Investigation, Denver Regional Office, Special Agent in Charge Calvin Shivers. "The FBI will continue to work with the U.S. Attorney's Office in Wyoming to hold individuals who commit health care fraud, at the expense of the U.S. government and hardworking taxpayers, accountable for their actions."

The Federal Bureau of Investigation and the Wyoming Medicaid Fraud Control Unit investigated this case. Assistant U.S. Attorney Eric Heimann of the U.S. Attorney’s Office for the District of Wyoming and Special Assistant United States Attorney Travis Kirchhefer of the Wyoming Medicaid Fraud Control Unit prosecuted the case.

Dr. John R. Sink, Jr., and Diane M. Sink are scheduled for sentencing on December 4th, 2018 in Cheyenne, Wyoming.

Suspected fraud against Medicaid or Medicare can be reported to the U.S. Department of Health and Human Services’ Office of Inspector General at 1-800-HHS-TIPS (1-800-447-8477) and the agency’s website Wyoming residents can call the Wyoming Medicaid Fraud Control Unit toll free at 1-800-378-0345, or visit their website at

Updated September 26, 2018

Health Care Fraud
Press Release Number: 18-043