WAUKEGAN, Ill. (STMW) — Robert Bostic was convicted Thursday of gunning down another man during a 1982 dispute over a drinking bet in the northwest suburban hangout of Bostic’s former motorcycle club.

A Lake County jury deliberated for about three hours before determining the now 71-year-old killed Carlton Richmond because he couldn’t pay a $500 wager Bostic claimed after chugging a fifth of Jack Daniels whiskey.

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The guilty verdict delivered by the nine-woman, three-man jury likely means Bostic faces between 20 and 60 years in prison, the Sun-Times is reporting.

He sat quietly next to his attorneys as the guilty verdict was read following a four-day trial. His son slammed his hand down on a wall and started sobbing.

The June 25, 1982, killing went unsolved for decades — largely because members of “The Wheelmen” biker club told police they didn’t see the shooting, even though several acknowledged they were at the clubhouse when Richmond was gunned down, authorities said.

Bostic, who now lives in Kingston, Tenn., was arrested in January after officials said four witnesses with ties to the club offered new information linking him to the killing.

“This defendant did something really, really stupid. He killed Carl Richmond in cold blood,” prosecutor Ken LaRue told jurors Thursday before they began deliberating.

Richmond, a 31-year-old restaurant manager, sometimes hung out at the clubhouse but wasn’t a member of the group, authorities said.

While the shooting angered club members because it drew police attention to the biker group, LaRue argued, they still closed ranks to try to protect Bostic by not cooperating with police.

“This is the beginning of a cover-up by the Wheelmen and the defendant,” LaRue said. “They’re still dealing with it because of the stupidity of this defendant.”

The case against Bostic, though, was hampered after his arrest when some recanted their purported statements about the shooting.

Several former club members denied during the trial that they offered any new information linking Bostic to the slaying when they were re-interviewed by police last year.

“I told him pretty much nothing. I didn’t remember much from that long ago,” John Winandy testified, describing his questioning last November by Round Lake Beach detective Gary Lunn.

But Lunn testified Winandy claimed he saw Bostic standing “a few feet” from Richmond just after the shooting and heard the dying man exclaim “you shot me.”

Lunn, however, acknowledged Winandy was never asked to make a written statement detailing his new claims.

A key prosecution witness, prospective club member Kevin Williamson, testified he heard a loud noise, then turned and saw Richmond grab his chest and look at Bostic standing close by.

Before Richmond collapsed, he exclaimed, “the S.O.B. shot me,” Williamson testified.

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“He told you what happened in that clubhouse,” LaRue said, describing Williamson as “the only member of the Wheelmen who testified truthfully.”

Defense attorney Joe and Michael Salvi blasted police — and Lunn especially — for not taking written statements supporting the purported information given by former club members.

“He doesn’t want any statements. He’s going to write the statements himself — how convenient” Michael Salvi said of Lunn.

A crucial part of the case involved recorded phone calls Bostic made from the Lake County Jail after his arrest.

On the calls — five of which were played for jurors during the trial — Bostic was pushing friends and relatives to make sure the former club members stuck to their original claims that they didn’t see the shooting, prosecutors argued.

“Tell them to say the same story they said the last time, you know,” Bostic said in a May 21 phone call to a friend, whom officials didn’t identify.

Those attempts to influence witnesses showed Bostic was guilty, prosecutors contended.

“An innocent mind doesn’t need to reach out to anyone who will listen to get them to change their testimony,” prosecutor Britta Peffer.

Salvi, though, argued Bostic only was trying to make sure his former colleagues told the truth about the shooting.

“He’s reacting to what’s perceived to be a railroading,” Salvi said, flatly telling jurors Bostic didn’t carry out the shooting.

“He is not guilty. I plead with you to render a verdict of not guilty,” Salvi said.

Salvi noted that police never found the murder weapon — or even an empty bottle of Jack Daniel in the clubhouse after the shooting to support claims that the shooting occurred over a bet.

“There was no physical evidence, no fingerprints, no whiskey bottle,” Salvi said. “There was no evidence against Bobby for 28 years.”

LaRue argued that club members had time to clean up before police arrived, noting Bostic himself left the clubhouse.

The club members, he added, didn’t even hurry to assist Richmond after he fell wounded to the floor.

“They kept drinking,” LaRue said.

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(Source: Sun-Times Media Wire © Chicago Sun-Times 2010. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)