GOLDEN, Colo. (KDVR) — A 47-year-old Littleton man was sentenced Wednesday to 30 years in prison for the murder of his wife in 2020, the First Judicial District Attorney’s Office announced Friday.

Scott Lee Smith II pled guilty to second-degree murder on Feb. 9. He was originally charged with first-degree murder and tampering with physical evidence in late September of 2021, according to the DA’s office.

A nearly yearlong investigation determined Smith killed 46-year-old Kanokwan “Nok” Smith, the release said. He was arrested and charged on Sept. 24, 2021.

Smith told police he shot and killed his wife in self-defense

The Jefferson County Sheriff’s Office responded to Smith’s 911 call on Nov. 1, 2020, of him telling dispatch that he just shot his wife in self-defense as she was trying to stab him with a butcher knife, according to the DA’s office.

Smith was taken into custody the next day but released five days later due to a lack of evidence for charges, the release said.

The investigation did not end after Smith’s release. Jeffco detectives continued to pursue the case and discovered Smith called his mother while he was in custody and asked her to get hidden surveillance cameras around his home. Investigators later found that the strategically located cameras were missing.

Smith’s mother, 67-year-old Theresa Rino, was arrested on Sept. 30, 2021, on charges of accessory to a crime, attempted tampering with evidence and conspiracy to commit tampering with evidence. Rino plead not guilty and was scheduled to be in court Friday.

Smith’s history with his wife

In court, Chief Deputy District Attorney Tyra Forbes explained that there was evidence showing Smith planned his wife’s murder. The release said Forbes told the court Smith had surveillance on his wife, had odd calendar reminders and was intensely involved in figuring out what would happen to his wife’s money when their divorce was final.

Forbes noted that Smith was working as a mental health counselor at the time and his wife worked multiple jobs to support the family, the release said.

“Smith also exhibited highly suspicious behavior on the day of the murder,” Forbes said in the release. “He texted Nok instructing her to put her ring in the safe, halted payment on a check, and several hours before the 911 call, he no call/no showed a longstanding weekly therapy session.”

Allegedly Smith’s wife was afraid of him, according to Forbes, and that family and friends told police of her fear and that she was trying to get away from him. But despite their pending divorce, she allowed him to live in the basement of their home, according to the details in the release.