A lot of movies purport to be "based on a true story," even
when the finished product is highly fictionalized. Are there any rules or
guidelines
that govern the use of this label?
–Ellie Kane
Not really. The "based on the true story…" tagline has become something
of a cliché for television movies-of-the-week, along with its insidious
variants: "inspired by…", "in the vein of…" and the
rest. You’re right in assuming that the phrase means almost nothing anymore.
I suppose a very bored, very litigious television viewer could sue a television
network claiming false advertising if the movie was really nothing like the "actual
events" it was based on, but what are the damages, really? Two hours wasted?
The only person who could legitimately claim damages is one of the "real
people" portrayed in the movie, under libel law. That’s why a network
legal department is careful to check out both the script and the marketing
to make sure that none of the portrayals could bring on a lawsuit.