It appears that even the office of the prime minister of the UK is interested in strategies for mapping argument, in this instance public argument and debate about political, economic, and social issues.
David Price has software. He calls it Debatemapper. It is online software ("cloud software"?). It is free. Go to http://www.debatemapper.com to get the story (and the software) firsthand.
Your assignment, dear Reader: Discuss the links between Debatemapper and procedures such as neo-Wigmorean charting of inferential argument from and about evidence! (Thank you.)