Web of Evidence (aka Beyond This Place, 1959).

In Web of Evidence Van Johnson returns to the United Kingdom after a long absence to find his father imprisoned for murder and becomes convinced of his father's innocence. Based on the novel Beyond This Place (1950) by A.J. Cronin (The Citadel, The Keys of the Kingdom, etc.), the film costars Vera Miles, Bernard Lee, Emlyn Williams, and Leo McKern.