DALLAS (CBSDFW.COM) – In what seemed to be record time, a Dallas jury found Thomas Johnson guilty of murdering a jogger in East Dallas in 2015.

After hearing closing arguments that totaled about 5 minutes — for both prosecution and defense — the jury deliberated for less than 15 minutes and confirmed that Johnson was the man who attacked David Stevens on the White Rock Trail, stabbing him to death with a machete.

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(credit: CBSDFW.COM)

The court heard from a forensic biologist regarding DNA and the trauma surgeon who treated Stevens on the morning he was attacked before State rested their case around 9:30 a.m. The defense rested without calling any witnesses.

Defense attorney Paul Johnson then questioned Johnson, on the record, regarding his mental health history, but the defendant did not take the stand. During the closing Johnson basically conceded that a guilty verdict would be reached, but said the real question was “what would be the appropriate punishment.”

It took nearly four years for the case to go before a jury, because Johnson was found to be mentally incompetent to stand trial in 2016. He was sent to a psychiatric hospital for evaluation and treatment and was later deemed to be competent.

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(credit: Jennifer Lindgren/CBS 11 News)

On the day of the stabbing avid runner David Stevens, 53, was out for a morning jog before going to his job at General Electric, where he worked as an engineer. Days after his death, Stevens’s wife, Patti, was found dead in her garage. Officials later determined the 44-year-old woman had taken her own life.

Before both sides rested, co-workers took the stand to talk about how Stevens always worked to be the best at whatever he undertook and was a ‘catalyst’ who made others around him better. One manager testified that since the deaths most of the once close knit team have moved on to other jobs.

Defense attorneys are bringing Johnson’s mental health to the forefront during the punishment phase of the murder trail, which is underway now.

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Thomas is facing up to life in prison now that he’s been convicted.