This is very cryptic SB:
Why don't you search for his death certificate? around 1962
Would you care to be more specific? Supply district, volume and page numbers perhaps?
Is this correct Emma? Did your James die "around" 1962? Death certificates generally contain the least information and are more likely to record inaccurate details. It won't give further information about his arrest and conviction.
A few quick thoughts:
Do you have James on the 1939 register? There may be clues as to his whereabouts - perhaps he had previous "form".
I am surprised that you could find no mention of him in the newspapers of the time. This is where you would expect to find what you are looking for re his crime. Maybe another set of eyes might locate something for you. His surname may have been misspelled, for example ...
What was his wife's name?
It sounds like this is a family story - I am wondering if there may be some inaccuracies.