Given Robert De Niro's commitment to method acting, you have to wonder if the bong hit he took in 'Jackie Brown' (1997) - Quentin Tarantino's blaxploitation homage - was authentic. After all, De Niro - who turns 73 today - moonlighted as a cabbie to research his role for 'Taxi Driver' (1976). And he put on 60 pounds to play boxer Jake La Motta in 'Raging Bull' (1980). Filling a bowl with real marijuana doesn't seem too extreme in comparison.

The hacking cough that erupts after his character - hardened criminal Louis Gara - takes a long puff sounds eerily authentic, don't you think?

Sadly, De Niro hasn't commented on the authenticity of the scene, but he did have another memorable marijuana moment a few years later in 'Meet the Parents' (2000). As retired CIA counterintelligence agent Jack Byrnes, De Niro struggles to get along with his daughter's goofy boyfriend Gaylord "Greg" Focker (Ben Stiller). At one point, the two strike up a rapport while listening to the folk classic Puff the Magic Dragon by Peter, Paul and Mary.

However, the new bond is quickly broken when Greg brings up the song's alleged cannabis connection.

"Some people think that...'Puff the Magic Dragon' means to really...um, to smoke uh...marijuana cigarette," Stiller stammers while miming a joint.

"Puff's just the name of the boy's magical dragon," De Niro says, following up his deadpan answer by lapsing back into his role as CIA interrogator. "Are you a pothead, Focker?"

Check out the full scene below. 

http://youtu.be/E99ncRTvhQ0?t=1m23s
And as a bonus, we've included De Niro's third contribution to cannabis culture: Zac Efron and Dave Franco impersonate his famous characters in the stoner comedy Neighbors (2014).

Banner image: Actor Robert De Niro attends the premiere to promote the movie 'The Good Shepherd' during the 57th Berlin International Film Festival on February 10, 2007 in Berlin, Germany (Denis Makarenko / Shutterstock.com)