Activity in the U.S. Attorney's Office

Possession of Child Pornography

Sean Joseph Brennan, 58, of Hudson, Wyoming, was sentenced to 120 months in federal prison with 10 years of supervised release to follow for possession of child pornography, subsequent offense. The court ordered restitution of $33,000 to be paid to the victims identified in the child pornography Brennan possessed. According to court documents, on Sept. 10, 2024, the Wyoming Division of Criminal Investigation (DCI) Internet Crimes Against Children (ICAC) task force was contacted by the Lander Police Department (LPD) who requested assistance with an investigation. LPD received information that Brennan had been engaged in online chats with an individual Brennan believed to be 13 years old. As part of their investigation, detectives were granted search warrants for his property and seized electronic devices containing thousands of images and videos of child sexual assault material, or CSAM. DCI – ICAC and LPD investigated the crime. Assistant U.S. Attorney Z. Seth Griswold prosecuted the case. The defendant was indicted on Nov. 20, 2024, and pleaded guilty on April 3. U.S. District Court Judge Alan B. Johnson imposed the sentence on June 25 in Cheyenne. Case No. 24-CR-00166

Drug Trafficking

Tyler Kihlstrom, 35, of Gillette, Wyoming, was sentenced to 168 months in federal prison with five years of supervised release to follow for conspiring to distribute 500 grams or more of methamphetamine. According to court documents, from March 2024 through May 29, 2024, Kihlstrom, along with others in Wyoming and Colorado, conspired to obtain methamphetamine in Colorado and distribute it in Wyoming. In May, after agents conducted several controlled purchases from Kihlstrom, he was pulled over and arrested near Douglas. He was found in possession of 549 grams of methamphetamine and over $8,000 in U.S. currency. The Wyoming Division of Criminal Investigation investigated the crime. Assistant U.S. Attorney Cameron J. Cook prosecuted the case. Kihlstrom was indicted on July 18, 2024, and pleaded guilty on Dec. 2, 2024. Chief U.S. District Court Judge Kelly H. Rankin imposed the sentence on June 26 in Cheyenne. Case No. 24-00103.

Illegal Reentry

Jorge Perez-Romero, 51, of Mexico, was sentenced to time served and will be deported for illegal reentry into the United States. According to court documents, on April 6, 2025, Perez-Romero was arrested by the Wyoming Highway Patrol for traffic-related offenses. Immigration and Customs Enforcement (ICE) was contacted, and they determined that Perez-Romero had previously been removed from the U.S. and had not applied for permission to reenter after being formally removed in June 2005. ICE investigated the crime, and Assistant U.S. Attorney Cameron J. Cook prosecuted the case. U.S. District Court Judge Alan B. Johnson imposed the sentence in Cheyenne on June 24. Case No. 25-CR-00077

About the United States Attorney’s Office

The United States Attorney’s Office is responsible for representing the federal government in virtually all litigation involving the United States in the District of Wyoming, including all criminal prosecutions for violations of federal law, civil lawsuits brought by or against the government, and actions to collect judgments and restitution on behalf of victims and taxpayers. The Office is involved in several programs designed to make our communities safer. They include:

Project Safe Childhood
Project Safe Childhood (PSC) is a DOJ initiative that combats the proliferation of technology-facilitated sexual exploitation crimes against children. The threat of sexual predators soliciting children for sexual contact is well-known and serious.

Operation Take Back America
Operation Take Back America is a nationwide initiative that marshals the full resources of the Department of Justice to repel the invasion of illegal immigration, achieve the total elimination of cartels and transnational criminal organizations (TCOs), and protect our communities from the perpetrators of violent crime. It also streamlines efforts and resources from the Department’s Organized Crime Drug Enforcement Task Forces (OCDETFs) and Project Safe Neighborhood (PSN).

Victim Witness Program
The Victim Witness Coordinator for the United States Attorney’s Office for the District of Wyoming is dedicated to ensuring victims of federal crimes and their family members are treated with compassion, fairness, and respect.

To report a federal crime, go to: https://www.justice.gov/actioncenter/report-crime