Meryl Streep, Johnny Depp, Justin Bieber Want You to See 

Meryl Streep, Johnny Depp, and Justin Bieber are among the latest notable figures who have joined the effort to help get the R rating of the documentary Bully changed, according toThe Hollywood Reporter.

Along with renowned Proposition 8 attorney David Boies and his daughter Mary, Streep and one of her daughters, actress Mamie Gummer, will cohost a screening of the Lee Hirsch-directed documentary in New York City March 20. The Reporter reveals that Depp has also offered his assistance and designer Tommy Hilfiger will design a T-shirt inspired by the poster for the film.

Teen idol Justin Bieber, himself a victim of antigay slurs, took to his Twitter account to educate his followers about the movie, encouraging them to stand up for each other and is currently discussing with The Weinstein Company how he can draw more attention to the film.

Ellen DeGeneres, singer-actress Demi Lovato, New Orleans Saints quarterback Drew Brees, and 20 members of Congress have all signed a petition launched by Michigan high school student Katy Butler to urge the Motion Picture Association of America to change the film's rating to PG-13 so as to allow the documentary to be seen by a younger audience. Anderson Cooper and Kelly Ripa hosted a screening of the film last week in New York.

Significantly, Gerry Lopez, CEO of AMC Theaters, has also spoken against the film's restrictive rating. "To automatically default Bully is a mistake," Lopez says in a statement. "Automatic default to a rating, a category, a genre ... doesn't matter, is a mistake. The message, the movie and its social relevance defy that kind of formulaic, conventional thinking. AMC will show this movie, and we invite our guests to engage in the dialogue its relevant message will inevitably provoke."

Bully will be released March 30. Sign Butler's petition here.