Haggard and dirty as he was, there was a certain aloofness, a dignity even, about the misshapen figure which struck Marcella strangely.

Both criminal and victim may have it--this dignity.

It means that a man feels himself set apart from his kind.
Hurd started at sight of Marcella.

"I want to speak to her," he said hoarsely, as the inspector approached him--"to that lady"-- nodding towards her.
"Very well," said the inspector; "only it is my duty to warn you that anything you say now will be taken down and used as evidence at the inquest." Marcella came near.

As she stood in front of him, one trembling ungloved hand crossed over the other, the diamond in her engagement ring catching the light from the window sparkled brightly, diverting even for the moment the eyes of the little fellow against whom her skirts were brushing.
"Ee might ha' killed me just as well as I killed 'im," said Hurd, bending over to her and speaking with difficulty from the dryness of his mouth.