Mary Barton discussion

Did it occur to anyone else how totally remiss it was of several men not to step forward and admit that they'd plotted the murder of Harry Carson as a whole group? Sure, they didn't know who drew the marked piece of paper, but they did know that some anonymous member of their group had pledged to kill Harry, and most likely did!

I was disappointed in them all, to think they could see an innocent young man, who wasn't even a member of their union, get arrested for execution without making any attempt to speak up and save him. Do you think Elizabeth Gaskell overlooked their knowledge and culpability herself, when she wrote it in such a way that the only chance to save Jem was through Mary's actions?