Man Who Killed Neighbor Over Tree-Trimming Feud Has No Regrets

— -- From inside the California jail where he is awaiting sentencing, Michael Vilkin said that given the chance, he would not change anything about the day he killed his neighbor John Upton.

“I’m not a kind of person who, if you spit in my face, I will not … just turn around and leave,” Vilkin, 62, told ABC News’ “20/20.” “And Upton was, figuratively speaking, spitting in my face the whole year.”

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A jury found him guilty of murder in the first-degree and assault with a deadly weapon last month. He faces 25 years to life in prison for the first-degree murder charge.

Vilkin and Upton, 56, had been arguing for over a year about Vilkin’s landscaping efforts on his property in Encinitas, California. The focus of their dispute was a narrow strip of land on Vilkin’s property in front of Upton’s rental home, where Vilkin was attempting to clear Brazilian pepper-trees.

“I wanted to clear the land from the wood and to build a house there,” Vilkin said.

On March 28, 2013, the neighbors’ dispute took a fatal turn. Vilkin shot Upton while he was outside on Vilkin's driveway, first in his midsection and then in his head.

Upton, a documentary filmmaker and philanthropist, was profiled on ABC News’ “20/20” in 1993 for his mission to rescue hundreds of deformed Romanian orphans. But while friends and family saw him as a hero, Vilkin said he was afraid of Upton.

“No, he did not [raise a hand at me]. But I was afraid of him, really afraid because he was roaring at me, he was yelling at me,” Vilkin said. “He acted like a gangster, like a tough guy, like a Mafioso. I believe that he was a Mafioso.”

Vilkin told police he believed Upton was carrying a gun and shot him in self-defense, but police found no evidence of a second gun at the scene.

“I was shooting. I did not aim. It was very close,” Vilkin said. “I expected to act in self-defense.”

Having already spent 18 months in jail, Vilkin said he will appeal the jury’s decision, saying his lawyer was incompetent.

“I’m always hopeful,” Vilkin said, “unless I see a pistol in your hand. Then I will shoot you in one second.”