UPDATED 04/06/12 12:21 p.m.
CHICAGO (CBS) -- A judge is set to rule Friday on whether to appoint a special prosecutor in a politically-charged case involving the nephew of retired Mayor Richard M. Daley.
Cook County Judge Michael Toomin is set to issue the ruling in the case of the family of David Koschman.
Early on the morning of April 25, 2004, Koschman reportedly had a confrontation with Daley nephew Richard "R.J." Vanecko outside a bar in the Rush and Division Street nightclub district. The quarrel allegedly prompted Vanecko to punch Koschman.
LISTEN: WBBM Newsradio's Lisa Fielding reports
Koschman had hit his head on the ground, and he died 12 days later. His mother, Nancy Koschman, says the punch by Vanecko led to her son's death.
His death was ruled a homicide, but no one was ever charged.
Detectives reportedly determined Koschman was the aggressor, based on witness accounts. But those witnesses later said they never told police Koschman was the aggressor.
Cook County State's Attorney Anita Alvarez's office also declined to press charges, saying there was not enough evidence to sustain criminal charges against Vanecko. But last year, Alvarez did ask Illinois State Police to examine the Chicago Police investigation.
Koschman's family's petition for a special prosecutor noted irregularities in the investigation, including false official reports and a case file that went missing, and says the investigation might have been influenced by Vanecko's relationship to Mayor Daley. The petition said the irregularities require an independent investigation.
The Better Government Association has filed an amicus brief in the case, and is urging Judge Toomin to appoint a special prosecutor.
"We basically said that we believe there needs to be an independent prosecutor. The family of every victim of violence is entitled to an investigation that is fair, thorough, impartial, and free of political considerations," BGA executive director Andy Shaw told WBBM Newsradio earlier this week. "This one just has too many questions."
Shaw the goal is not to go after Vanecko, but to provide solace for the Koschman family.
"We're not trying to convict Mr. Vanecko or even get him indicted," Shaw said. "We're saying the Koschman family deserves closure here."
Vanecko denies any wrongdoing.
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