The federal sentences followed convictions for drug, firearms and obstruction crimes, while a judge separately found that Floyd Coates caused Sramek’s death.

SIOUX CITY, Iowa — Two men tied to the 2019 disappearance of 18-year-old Sunny Sramek have been sentenced to a combined 45 years in federal prison, bringing a major court proceeding to an end more than seven years after the Nebraska teenager left home and was never seen again.

Floyd Clifford Coates Jr. received 35 years in federal prison after a jury convicted him of offenses involving methamphetamine trafficking, firearms and the concealment of evidence. Dennis Lawson received a 10-year sentence for threatening a witness in an effort to stop information from reaching authorities. Neither man was convicted of murdering Sramek. At Coates’ sentencing, however, U.S. District Judge Leonard T. Strand found that Coates intentionally caused Sramek’s death and then covered up what happened, according to federal prosecutors.

The sentences capped a case that began April 20, 2019, when Sramek left Trenton, Nebraska, in a white 2004 Ford Explorer. She had told friends and family that she expected to take a day trip to Omaha with Coates. The FBI later said there had been no reported sighting or contact from Sramek after she left. She was reported missing by her mother the following day, and federal investigators eventually joined local and state authorities in trying to determine where she had gone and what had happened to her.

Evidence presented during an 11-day federal trial in Sioux City showed that Sramek’s trip overlapped with a drug run Coates had organized over Easter weekend in 2019. Prosecutors said Coates was part of an organization moving pounds of methamphetamine from Colorado into Iowa for redistribution. He arranged for an Iowa woman to drive from Sioux City to Blair, Nebraska, where she was supposed to meet him before continuing to Kansas City, Missouri. Sramek, meanwhile, traveled with Coates from Trenton to Blair. Prosecutors said there was no evidence that Sramek knew about the planned Kansas City trip.

The driver testified that when she arrived in Blair, she saw Sramek motionless inside the Ford Explorer. According to the government’s account of the trial, Coates told the woman that he had given Sramek methamphetamine and said she had overdosed. Instead of continuing to Kansas City, Coates canceled the planned drug trip and directed the driver toward Lawson’s rural property near Whiting, Iowa, along the Missouri River. The witness said Coates and Lawson went away together for a period after arriving. When they returned, she testified, Sramek’s body was no longer there.

The witness also described helping clean the Explorer. Prosecutors said Lawson warned her against talking about what she had seen, telling her, “If you talk, it’s your funeral.” That statement later became central to the federal obstruction case against Lawson. Jurors convicted him of using a threat of physical force to hinder or prevent communication with federal law enforcement or a federal judge. He was acquitted of other charges involving drugs, threats and obstruction.

Investigators never recovered Sramek’s body, but prosecutors built their case from physical evidence, witness testimony and statements attributed to Coates. Federal forensic analysis identified Sramek’s DNA and a significant amount of blood inside the Explorer, according to the Justice Department. Evidence also indicated that she had struggled inside the vehicle. An FBI geologist testified about damage to a window that investigators said was consistent with impacts from inside the SUV, while medical testimony addressed symptoms witnesses described seeing before Sramek disappeared.

Prosecutors also presented evidence that Coates gave different accounts of Sramek’s death after she disappeared. He told some people that she had died from a methamphetamine overdose and gave others a different, more violent account, according to the government. Federal officials said the versions shared one detail: Coates claimed that Sramek’s body had been put into the Missouri River to hide evidence. Witnesses also testified that Coates expressed confidence that the absence of a body would protect him, including the statement, “No body, no case.” The body has not been found.

The federal prosecution did not result in a murder conviction. Instead, the government pursued charges it said could be proved through evidence surrounding Coates’ drug operation, firearms and efforts to conceal objects connected with an official proceeding, along with Lawson’s threat against the witness. Jurors returned their verdicts Nov. 25, 2025, after about two hours of deliberation. Coates was convicted on six counts, while Lawson was convicted on the single witness-threat count. Both men were acquitted of additional charges.

The sentencing phase added an important finding that went beyond the offenses listed in Coates’ convictions. According to prosecutors, Strand concluded that Coates had intentionally caused Sramek’s death and covered it up. The finding was made by the judge in determining Coates’ federal sentence and should not be confused with a jury conviction for homicide. Coates received 35 years in prison followed by five years of supervised release. Lawson received 10 years in prison and three years of supervised release. Federal sentences do not include parole.

Federal officials described the case as the result of years of work by agencies in Nebraska, Iowa and Kansas. The investigation involved the FBI, the Bureau of Alcohol, Tobacco, Firearms and Explosives, the Nebraska State Patrol, Iowa investigators, local sheriff’s offices, the Iowa medical examiner’s office and other agencies. At trial, the government relied on more than the fact that Sramek had last been seen with Coates. Prosecutors presented the Explorer, forensic findings, the testimony of the Iowa driver and people who said Coates discussed what happened afterward.

The prosecution also marked a change from the early stage of the investigation, when authorities publicly treated Sramek as a missing person and appealed for information. In June 2019, the FBI said she had last been seen in Trenton on April 20 and had not contacted anyone since. The bureau publicized the white Ford Explorer and other identifying information as investigators searched for leads. Years later, the federal case reconstructed a much more detailed timeline of her final known trip, including the stop in Blair and the movement toward Lawson’s Iowa property.

U.S. Attorney Leif Olson said after sentencing that the investigators had continued pursuing the case despite the passage of more than seven years. FBI officials likewise credited the persistence of agents, officers and prosecutors involved in the search for Sramek and the effort to determine who was responsible for concealing what happened. The sentences do not resolve one of the case’s most painful unanswered questions: Sramek’s remains have never been recovered.

Coates and Lawson remained in U.S. Marshals Service custody following sentencing pending transportation to federal prison. Their convictions and sentences establish criminal responsibility for the federal drug, firearms and obstruction offenses proved at trial, while Sramek’s disappearance remains defined by the absence of her recovered body and by the judge’s sentencing finding that Coates caused her death.

Author note: Last updated Aug. 26, 2026.