Every cold case homicide and missing person case represents a tragic and unexplained loss. These victims deserve justice. Their families deserve answers and closure. That’s why tackling Boulder County’s cold cases is a priority for me as your district attorney.

I am excited to announce the formation of a Cold Case Unit within the DA’s Office that will work closely with law enforcement to review unsolved homicide and missing person cases. With our Cold Case Unit, and the strong support of law enforcement in Boulder County, I look forward to doing everything we can to solve these haunting cases.

After becoming your district attorney, I announced my long-term goals for our office — including our new Conviction Integrity Unit. Another priority is solving cold cases. As part of this effort, the Colorado Bureau of Investigation provided me with the list of more than 30 cold cases that remain unsolved in Boulder County. Although the Boulder DA’s Office and law enforcement have been successful in solving cold cases over the past nine years, we still have more to do.

They are “cold cases” because a year or more has passed since the victim died or was reported missing. Despite intensive efforts, law enforcement and prosecutors have been unable to develop sufficient evidence to explain what happened, or to name and arrest the people responsible. The trail has seemingly gone cold.

Each case on the list is a long, terrible story of heartbreak and unanswered questions — like Frank Santos, killed in 2004 while driving his car along U.S. 36, whose murder remains unsolved. Each represents a victim gone — including 6-year-old Tiannah Annibal, believed to have been taken from her home in Longmont in 2013 by a non-custodial parent.

Over the course of my 20 years as a prosecutor, I have worked directly on solving cold cases. As a member of the Colorado Cold Case Review Team — a statewide group that assists local law enforcement agencies to reexamine cold cases — I have engaged in the process of reanalyzing cold cases, with an eye towards applying new scientific advances and creative approaches. As the second-in-command of the Jefferson/Gilpin County DA’s Office, we utilized a “solvability factor” analysis for reviewing cold cases.

These successful experiences have demonstrated that the trail is never cold. I value the strong support for the unit from our law enforcement agencies who have been engaged in these investigations — sometimes for more than a decade. Our collaborative efforts will bring renewed energy and strength to the resolution of these cases.

The Cold Case Unit will be led by Chief Trial Deputy Fred Johnson and Senior Investigator Gary Thatcher. Each brings outstanding experience and knowledge to this effort. Johnson currently is assisting as a special prosecutor in the Dylan Redwine case. Thirteen-year-old Dylan was killed in 2012 in La Plata County and, after an intensive cold case investigation, his father was charged with murder. Thatcher has worked on cold case investigations and served as the lead detective in the Scott Kimball serial murder cases.

Our Cold Case Unit will conduct an initial review of cold cases, together with detectives from the investigating agencies. The overarching goal will be to look at the facts and evidence with fresh eyes and an open mind, armed with the latest developments in forensic science. Using this approach, additional resources will be allocated as leads or investigative techniques are pursued.

Johnson and Thatcher also have now been invited to join the statewide Cold Case Review Team. Their participation certainly will benefit the review team’s work in enhancing cold case investigations across Colorado. But it also will benefit our Cold Case Unit, as they bring back ideas, innovations and resources that could be applied here.

The 1996 murder of 6-year-old JonBenet Ramsey is one of the cases on the list maintained by the Colorado Bureau of Investigation. Her death sparked prolonged interest that persists to this day. Significant resources have been expended trying to determine who killed her, but the case remains unsolved. The Boulder Police Department continues to assess active leads in connection with that murder.

Our mission will be to provide the investigative focus given to the Ramsey case to all the cases under review. While some of these cases have received less media attention than others, none of them is any less important or tragic. For every one of these cases, we hope to secure justice for the victim, closure for their loved ones, and answers for our community.

Michael T. Dougherty is Boulder County’s district attorney.