The key hurdles to filing charges in 2004, according to Yawger:
After punching Koschman, Vanecko ran off with a friend, Craig Denham. Two other Vanecko friends who were there — Kevin McCarthy and his wife, Bridget Higgins McCarthy — initially told the police they didn’t know the two guys who ran away. They didn’t admit they did know them until May 13, 2004, Yawger says — 18 days after Koschman got punched and seven days after he died in a hospital from brain injuries suffered when the back of his head hit the street.
Till then, the police hadn’t been able to identify Vanecko or Denham as being involved, according to Yawger.
via Koschman cop: Daley nephew, friends made charges impossible – Chicago Sun-Times.