How would the police prove Mary Maloney guilty?

[snowhitefox]

In Roald Dahl's "Lamb to the Slaughter", how would the police/forensics be able to prove Mary Maloney guilty of killing her husband? (I know that we are left hanging in the end, and it's suggested that she will get away with the crime, but I would like to know how she would be prosecuted.

[Anonymous]

In 1953 (when the story was written), it would be impossible for the police to prove anything unless someone actually saw Mary through a window committing the act.

In 2011, it may be possible for forensics to determine the exact time of death (checking against her alibi), the height/size of the attacker (in correspondence with the wound - size, shape, angle, depth, etc), the possibility of forced entry into the home and blood spatter on Mary.

[snowhitefox]

Thank you very much, sir. You helped me a lot.