Patrick has finally reduced his Red John list to only two
possible candidates. Let’s say Bob Kirkland and Walter Mashburn. Patrick removes
any references to Mashburn on his connection board, leaving Kirkland and six
other characters that he has already eliminated. After letting Red John copy the
information (Red Letter Day episode) and derive the planted list, he waits for
Red John to react. If Red John thinks Patrick is off the mark and he will stay
smugly silent. In that case, Mashburn is Red John.  If Red John is provoked into a violent
response because he feels Patrick is drawing close (Red John’s Rules), Patrick
concludes it must be Kirkland.