Rita Hayworth / Veronica Lake / Lauren Bacall
The film's Director of Animation Richard Williams gave an interview where he talked about the basis for Jessica's characterisation on screen. In short, she's a mish-mash of various famous Hollywood actresses.
Set in Los Angeles in 1947, "The Rabbit," as [Director of Animation] Mr. Williams calls the film, is essentially a buddy movie involving a down-at-the-heels private eye (Bob Hoskins) who reluctantly seeks to save Roger Rabbit, a hapless cartoon star wrongly accused of murder. A third key character is, of course, the femme fatale - Roger's impossibly gorgeous wife, Jessica.
"It's the ultimate male fantasy, drawn by a cartoonist," said Mr. Williams. "I tried to make her like Rita Hayworth; we took her hair from Veronica Lake, and Zemeckis kept saying, 'What about the look Lauren Bacall had?'"
New York Times - An Animator Breaks Old Rules And New Ground in 'Roger Rabbit'
Red Hot Riding Hood / Betty Boop / Gary K. Wolfe's wife
Gary K. Wolfe, the writer of the Roger Rabbit books was extensively involved in the production of the film, regularly meeting with the screenwriters and spending time with the animation team and director fleshing out the characters. In his mind, the character is largely based on Tex Avery's Red Hot Riding Hood. There was also more than a passing nod to Betty Boop in how Jessica was presented in the film.
Q. I've heard conflicting reports that (film version) Jessica Rabbit was based on 1) Actress Vikki Dougan or 2) Tex Avery’s cartoon character Red. Is one, the other or a combination of both?
"I based Jessica on my ideal of what a perfect girlfriend would be.
I've been told since them by many in the movie industry, that if
Jessica is my idea of a woman, perhaps I should stick to writing
Turkish prison or war movies where I don't have to deal with
"feminine" issues. I based Jessica on Tex Avery's cartoon character
Red Hot Riding Hood."
Gary K. Wolf (Creator of Roger Rabbit) Ask Me Anything session
Q: Is Jessica Rabbit an ideal woman creation of yours, or is she based on any one or multiple women?
GKW: Jessica Rabbit is my idea of the perfect woman. But you must remember that I was an only child, no sisters, and grew up in a small mid-western town with no girls. The only women I knew were elderly school teachers and maiden aunts. So I invented Jessica to [get] by. I based her on Tex Avery's Red Hot Riding Hood. In fact, if you watch that cartoon, you'll see RHRH doing a musical number which is a virtually [a] duplicate of the one Jessica does in the Ink and Paint Club. Incidentally, because of my lack of understanding of women, I have been advised more than once to limit my writing to war stories and Turkish Prison movies.
1995 Question and Answer IRC 'Meet with Gary Wolf
Q: Speaking of hidden things, what's the deal on the Jessica Rabbit cels that show a bit more than others?
I can't officially confirm that, but if I had to guess, I would say that it was the animators continuing an age-old tradition. Betty Boop was topless in six frames of every cartoon. If Betty can boop a doop, so can Jessica. If you actually see the scene, there's nothing really risque-like about it. It's the equivalent of peeking under the skirt of your Barbie doll. Animation is a very tedious business. Whatever animators can do to keep themselves enthusiastic, more power to them.
Q: How did you come up with the idea of Jessica Rabbit?
She's based on a Tex Avery character call Red Hot Riding Hood. Red Hot appeared in a number of cartoons in the forties and early fifties. Wild and Woolfy being the one I remember best.
Wednesday 6 August, 1997 - The Arbordale Auditorium on AmberThree Productions' EntertainMuck
Wolf also commented that Jessica was, in part, based on his wife. It's not clear if he was joking.
Q. Is there a special lady Jessica Rabbit is crafted after, or is she the best bits of several?
She's based on my wife. And now that I've admitted that, I don't want to see a hundred fan boys hanging around my front door.
On a related note, Vikki Dougan claimed in a 2009 interview with Exclusive Hollywood that the character of Jessica Rabbit was based on her, but that she was never officially credited as the inspiration. There doesn't appear to be any solid proof of this.
they did a caricature of me, everybody tells me and actually, you know what you're not going to believe this [but] I've never seen the movie.