The widow of an Australian man shot dead in Detroit last year has welcomed a jury verdict convicting US lottery millionaire Freddie Young of second degree murder.

Property developer Greg McNicol, 45, was killed in May last year outside an apartment building he owned.

Authorities said that Young, 63, drove to a 10-unit apartment complex on Detroit's east side that Mr McNicol had bought earlier in the year for just $US35,000.

Young's 20-year-old daughter was a tenant and Mr McNicol was evicting her for failure to pay rent and other issues.

Witnesses told the court earlier in the week that Young, who was part of a syndicate that won $US29 million in a lottery last February, drove up to the complex, pulled out a pistol and shot Mr McNicol at close range.

An autopsy found the bullet struck a major artery in Mr McNicol's pelvic area.

Mr McNichol's widow, Katie Scartezini-McNicol, has told ABC Local Radio she is relieved by the guilty verdict.

"It was nerve-wracking," she said.

"We didn't expect them to deliberate so quickly, but fortunately they came out with a guilty verdict."

Guilty of murder: Freddie Young ( AAP/Detroit Police Department )

Ms Scartezini-McNicol says she still does not know just why her husband was killed.

"I've been looking for an explanation since it happened because it's totally senseless and stupid," she said.

"But what some people told me is [Young] was intoxicated by the power of his money and he thought that he could do whatever he wanted."

In January, a Detroit judge abruptly ended the first murder trial after just four days.

That trial featured dramatic testimony from witnesses and a haunting 911 emergency call made by Mr McNicol, 45, who grew up on Victoria's Mornington Peninsula and moved to the US in 1998.