I want to write a movie script about a person with the intention of making a movie.
Almost all the information I have about him is from a book he wrote and published.
Do I need his permission, legally, to write the script and make a movie? I would credit his book at the end of the film.
Since your plan is to create a work based on an existing property, you absolutely do need permission (in the form of an 'option') to turn that book into a film. Since this individual is a celebrity and you're a nobody, they aren't going to give that to you for free, and you likely don't have the wherewithal in terms of legal support to create appropriate contracts or finance to pay them for the option, you're not going to get anywhere.
You may find this case that appeared in the UK courts to be instructive. A scriptwriter tried to write a movie script that was based on the life of a disabled football fan. Although they claimed that the script was 'fictionalised', the judge noted that it really wasn't.
A prior non-fiction book had been written about that same fan's life story and many of the same events occurred in both versions of the script and book. The judge ruled that because the script was an adaptation of the book, without the permission of the author the script couldn't be adapted into a film, nor could it be sold. It simply wasn't an original work, nor was it sufficiently transformative.
Additionally, the extra wrinkle comes from the fact that since the subject of your planned biopic is still alive, they could basically sue you for defamation over any incident (no matter how trivial) that portrays them in a bad light. It would be down to the producers to prove in court that the event took place precisely as shown on screen, or that every single audience member would be made aware that the events were entirely fictional.
In short, nobody in their right mind is going to want to touch your screenplay with a 10-foot bargepole.
First you say this:
Do I need his permission, legally, to write the script…
You don’t need to get his permission to write a script for your own personal purposes. You can do whatever you want. So if you want to spend the time and energy required to write a script? Go for it!
Then you say this:
…and make a movie?
There’s the rub! If you want to make a movie, the script becomes a product. If you are serious about this it is really a chicken / egg like situation: Which comes first? The script? Or the pitch to the author that you want to make a movie and would like his permission to write a script and make a movie?
Then you also say you this:
I would credit his book at the end of the film.
Whoa! Whoa! Ask yourself a few questions:
Because honestly, you sound like you don’t know what you are doing. You should stick to one role unless fate deems it best you be a multi-faceted auteur.
Here’s my final advice: Before going and asking for permission, would it be possible for you to write an outline or draft of the script?
You see, writing a full script is a lot of work. So rather than doing that, split the difference and write a solid outline or a draft of the script and then pitch that to him.
If he’s receptive, that’s great! If not, then no big deal; you wrote something short and sweet, pitched it and it didn’t hit.
This isn't how movies are made from books. The proper way to go about this is to pitch your movie idea/script to a movie studio. If the movie studio accepts your script, they will handle the legal side. You should take a screenwriting class that teaches both the craft of screenwriting and the business side. Be thoughtful when you look at class descriptions and email the department secretary before you decide to take the class.
Having your movie script accepted is difficult because of the competitive world making movies. It would be best if you build up your reputation as an accomplished writer by publishing your own, original work first.
My father, a retired attorney, has a favorite saying:
you can sue anybody over anything for any reason at any time. You may not win, but you can always sue.
If you'll forgive me for asking a rhetorical question, why wouldn't you want to collaborate with the subject of your movie? If you were writing an exposé, blowing a whistle or filming a tell-all it would make sense. But you said you're basing the film off a book the subject wrote and published.
Please tell me that I'm wrong, but off the top of my head, the only reasons someone would ask the question you're asking are...
You're sure they'll say no if you ask, or
You want control over the production and you expect they'll take it, or
You want more credit than you'd otherwise get, or
You don't want to split the proceeds.
The problem is, largely famous or not, celebrities have a brand they will often go to great lengths to protect.
A Düsseldorf court has sided with the famous rock musician. A German woman who had put up a single bootlegged CD of one of his concerts for €9.95 on eBay now has to pay major fees.
The decision was reached by the Düsseldorf regional court on Wednesday. The injunction issued on behalf of best-selling guitarist Eric Clapton forbids a woman from the town of Ratingen near Düsseldorf from selling a bootlegged recording of one of his concerts from the 1980s online. Clapton sent the court an affidavit stating that the recordings were illegal.
The defendant claimed she did not know she was infringing copyright when she put the recording for sale for €9.95 ($11.20) online and appealed to the court. The 55-year old claimed her late-husband told her he had purchased it in 1987 at a well-known department store.
Yet the appeal was rejected. The judge ruled that it did not matter that she hadn't purchased the CD herself and did not know the recording was done illegally, as German tabloid Bild reported. The injunction requires the defendant to pay the legal fees of both parties, which total approximately €3,400, according to the media outlet. If she continues to offer the CD for sale she faces a fine of €250,000 or six months in prison. (Source)
Successful brands are like fine crystal: a ton of work to make and easy to break. If the owner doesn't act to protect the brand it becomes easier for the next person to profit from it without compensating the owner.
Conclusion
Never pluck another person's golden goose without asking first.
