A Cook County judge denied a media request Wednesday to unseal a special prosecutor's report into the death of David Koschman before a nephew of former Mayor Richard Daley goes on trial on involuntary manslaughter charges.

Judge Michael Toomin said he would wait for the conclusion of Richard Vanecko's trial scheduled for February before making public the report of special prosecutor Dan Webb.

Webb released the report's key findings in September but asked to have the 162-page document temporarily sealed because it contained potentially explosive details about the investigation that could impair Vanecko's right to a fair trial.

The Chicago Sun-Times and the local NBC affiliate sought to unseal the report, but in his ruling, Toomin noted that three-fourths of the report concerns grand jury matters that typically are kept secret. The media outlets failed to satisfy any of the conditions under which grand jury proceedings would be made public before trial, the judge held.

The report details Webb's investigation into whether Chicago police or Cook County prosecutors improperly tried to protect Vanecko because of his connections. Webb decided against bringing any charges against police or prosecutors.

In his written ruling Wednesday, Toomin revealed that 24 witnesses appeared before the special grand jury, 10 of whom received immunity from prosecution after asserting their Fifth Amendment right against self-incrimination.

The judge also denied a request by the Fraternal Order of Police, the union representing Chicago police officers, to file a friend-of-the-court brief asking that Webb's report be permanently sealed. Toomin said the union was improperly trying to act "as an advocate in this matter" and was asking him to engage in "an unprecedented role of censorship."

Toomin had ruled earlier that the report also wouldn't be provided to Vanecko's defense team because of Webb's legal analysis and conclusions, but Thomas Breen, one of Vanecko's attorneys, said in court Wednesday that he intended to ask the judge to reconsider that decision. The grand jury testimony had previously been given to the defense.

Vanecko is scheduled to go to trial Feb. 18 on involuntary manslaughter charges in the death of Koschman, 21, of Mount Prospect, after a drunken confrontation Koschman and his friends had in the Rush Street night life district in April 2004 with a group that included Vanecko. Koschman was knocked to the ground and hit his head. He died 11 days later.

No charges were filed after the initial investigation, but the case was reopened in 2011 after a Sun-Times series raised questions about whether authorities hid evidence or failed to aggressively investigate Vanecko because of his ties to Daley. 

Vanecko was indicted last December after Toomin appointed Webb, a former U.S. attorney in Chicago, to investigate the case. 

sschmadeke@tribune.com