Men Linked to the Disappearance of an 18-Year-Old Nebraska Woman Found Guilty of Drug, Gun, and Obstruction-Related Charges

Two men with lengthy criminal histories were convicted by a jury on November 25, 2025, after a 11-day trial in federal court in Sioux City.

Floyd Clifford Coates, Jr., aka Cliff Coates, age 44, from St. Francis, Kansas, was convicted of Conspiracy to Distribute a Controlled Substance, Possession of a Firearm in Furtherance of a Drug Trafficking Crime, Possession of Ammunition by a Felon and Drug User, Conspiracy to Conceal Objects with the Intent to Impair Their Availability for an Official Proceeding, and Concealing Objects with the Intent to Impair their Availability for an Official Proceeding. Coates was acquitted of other charges related to threats, and obstruction of justice. 

Dennis Lawson, age 65, from Whiting, Iowa, was convicted of Using Threat of Physical Force Against Another with the Intent to Hinder, Delay, or Prevent the Communication to a Law Enforcement Officer and Judge of the United States of Information Relating to the Commission and Possible Commission of a Federal Offense. Lawson was acquitted of other charges relating to drugs, threats and obstruction. 

The verdict was returned following about 2 hours of jury deliberations.

The evidence at trial showed that in Spring 2019, Coates was a member of a drug trafficking organization that funneled pounds of methamphetamine from Colorado to Strubel, Iowa, among other places, for redistribution, and that Coates possessed firearms to protect his illegal drug operation. Evidence also showed that on Easter weekend 2019, Coates had arranged a drug run to Kansas City, Missouri.

To execute the Easter weekend drug run, Coates had convinced an Iowa woman to drive from Sioux City, Iowa; meet him in Blair, Nebraska; and drive him to Kansas City, Missouri, and back. Coates decided to travel to Blair from Trenton, Nebraska, with another woman, 18-year-old Sunny Sramek. Coates and Sramek left Trenton in his wife’s white Ford Explorer to go on the trip. There is no evidence Ms. Sramek knew Coates was going to Kansas City; in fact, she told friends and family that she was going to be on a day trip to Omaha. 

The pair made it to Blair, where Coates went into a home, but Ms. Sramek did not. Coates’s driver arrived from Sioux City and Coates said nothing of Ms. Sramek to the driver. As the driver and Coates left the home, the driver saw Ms. Sramek’s motionless body. The driver testified it looked as if Ms. Sramek had overdosed, and Coates said he had provided her methamphetamine. Coates cancelled his drug run to Kansas City and told his driver to go to the home of his brother-in-law Dennis Lawson near Whiting, Iowa, on the banks of the Missouri River. The driver testified that after they arrived at Lawson’s residence Lawson and Coates disappeared for a time, when they returned, Ms. Sramek’s body was gone. The driver also testified that she and Coates cleaned out the car, and that Lawson threatened her saying if she told anyone, “it would be her funeral.”

Later, Coates told confidants that Ms. Sramek had overdosed. He told other friends a more violent story. In both versions, however, he told people he had thrown Ms. Sramek’s body into the Missouri River to conceal evidence of his crimes. Coates was confident his efforts at concealing Ms. Sramek’s body would insulate him from accountability. He told one person “no body, no case” and asked another “you can’t get charged with murder if there is no body, can you?”

Coates’s confidence was misplaced. Law enforcement gathered a significant amount of physical evidence tying Coates to Ms. Sramek’s disappearance. Forensic analysis indicated Ms. Sramek’s DNA and a significant amount of blood were found in the white Ford Explorer. The forensic findings combined with other evidence provided the proof the jury used to convict Coates and Lawson. 

“Sunny Sramek went missing more than six years ago,” said United States Attorney Leif Olson. “But the investigators’ dedication kept her case from going cold. Thanks to them, these two criminals now face judgment for Sunny’s disappearance. Those who believe they can escape justice through threats, cover-ups, or the passage of time will discover they are mistaken.”

“The convictions of Coates and Lawson represent years of tireless, unwavering efforts by a dedicated team of FBI personnel who never stopped looking for Sunny Sramek,” said FBI Special Agent in Charge Eugene Kowel. “Despite the defendants’ best efforts to conceal involvement in her disappearance, the FBI persisted in our mission to hold these subjects accountable for their actions. We hope these convictions bring some measure of solace to Sunny’s family. The FBI will always use every tool and technique in our arsenal to seek justice for the missing and attempts to hinder those efforts will be aggressively investigated.”

Sentencing before United States District Court Chief Judge Leonard T. Strand will be set after a presentence report is prepared. Coates and Lawson remain in custody of the United States Marshal.

Coates faces a possible maximum sentence of life imprisonment and five years of supervised release following any imprisonment.

Lawson faces a possible maximum sentence of 20 years’ imprisonment and three years of supervised release following any imprisonment.

 The case was investigated by Hitchcock County, Nebraska, Sheriff’s Office; the Nebraska State Patrol; the Iowa Department of Public Safety—Division of Criminal Investigation; the Plymouth County, Iowa, Sheriff’s Office; the O’Brien County, Iowa, Sheriff’s Office; the Iowa Department of Natural Resources; the Iowa Office of the State Medical Examiner; the Goodland, Kansas, Police Department; and the United States Department of Justice’s Bureau of Alcohol Tobacco Firearms and Explosives (ATF) and Federal Bureau of Investigation (FBI). The case is being prosecuted by Assistant United States Attorney Forde Fairchild. 

 Court file information at https://ecf.iand.uscourts.gov/cgi-bin/login.pl.

The case number is 24-4021.

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