As a general rule executions should be public as in the olden days as a warning to others who seek to commit the same crimes as the condemned.
Something graphic and eye openning such as a beheading with axe or swaord or a hanging using the short drop method so the death is not instant but the condemned is seen struggling for air before their end.
Something graphic and eye openning such as a beheading with axe or swaord or a hanging using the short drop method so the death is not instant but the condemned is seen struggling for air before their end.