GRAND JUNCTION, Colo. (Court TV) — A Colorado man is standing trial for allegedly murdering his girlfriend’s 6-year-old son.

Darin Thrailkill, 40, was arrested in 2023 for the July 2016 death of Martin Osinski. He’s charged with first-degree murder and second-degree murder.

FILE – This 2023 booking photo provided by Grand Junction Police Department shows Darin Thrailkill. (Grand Junction Police Department)

An investigation began when the unresponsive boy was brought to St. Mary’s Hospital on July 2, 2016. Despite life-saving efforts, Osinski was declared deceased. An autopsy later ruled the manner of death a homicide.

The case remained under investigation for more than seven years before authorities obtained an arrest warrant for Thrailkill in October 2023, according to Grand Junction

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