Why are George and Chris arguing?

Chris says he's heard Steve's accusations before in court, but George says it was different hearing it directly from his father, a "frightened mouse" of a man who would never do such a thing on his own volition. Chris counters that he certainly would, and because he was such a frightened mouse he would throw the blame on someone else because he was not man enough to take the heat. George accuses Chris, saying that he must know the family secret, and that this is why his name is not on the business.