Ok, this is a good start.
One thing that bugged me was spelling pa "paw"--when I think of paw I think of the foot of a cat or dog. It was kind of jarring and took me out of the story a bit. I think it's spelled simply pa. The cops are none to gentle with him.
First, to is supposed to be too--but it might be better if you say not. Or this sentence might not be necessary because you show they aren't gentle in the next couple of sentences . . . maybe you could show more of how ungentle they are instead of telling us.
The cops seem to be awful mad at Paw. I look up at Momma, “What did Paw do?”
It seems awkward to have Paw twice so close together, maybe change the first one to him or the second on to he.
also, I think there could be a better connection between the first and the second sentence. Maybe you could have the man character tell us the cops were mad and then think about it--wondering and then venture out of his corner to ask. because he is in a corner, it seems as if he is trying to stay out of the way (which is great because I think that is something that a kid would do--great characterization) anyhow, because he seems to be trying to stay out of the way, it seems strange that he would just jump in and ask what his pa did. Maybe have him hesitated a bit--I'd imagine that the cops would be scary for him and he wouldn't want to be too close to them.
“They’re saying he killed Old Man Hinkle down at the station.”
I'm not a mother so I don't know, but I'd imagine that if I were in this situation, I wouldn't just tell my kid, especially with the cops there. It depends on how hold he is but I'd imagine that she'd tell him that she'd tell him later (I don't think a mother would just simply tell her child that his father is accused of murder.) Maybe you could have the child overhear it later or something.
“I don’t think he’d kill that nice old man."
I'm not sure who says this. Is it the mother or the boy? It's formatted as if the mother says it but sounds like something the boy would say.
I hope this was helpful and not too nit picky. You can send it to me and I'll take a look at the whole thing. It just might take me a while to get it back--college just started again and I unfortunately, I have to go to class and study and stuff--but I'd get to it as soon as I could.