Rivers and her daughter, Melissa, pioneered award-show red carpet coverage when, in 1996, the duo began hosting "Live From the Red Carpet'' for E! Entertainment Television.
After leaving the network in 2004, they returned in 2010 with "Fashion Police" where Rivers led a panel that critiqued style choices of the stars.
In her assessment of the best and worst dressed stars at the 2008 Oscars, Rivers said the form-fitting coppery gown worn by Faye Dunaway "wasn't really a dress — it was kind of like Spanx with sparkles on it." And when asked in a 2013 interview with The Associated Press what she thought of Adele's Grammy outfit, she replied that the singer "looked like she was sitting on a teapot."
"I think the most important thing that she did was add a sense of humour which is not really that present when you take yourself too seriously — which is probably what a lot of us do," said Randi Bergman, executive digital editor for Fashion Magazine.
Charlotte Herrold, associate fashion editor at Elle Canada, said that Rivers was able to get away with being brash on the red carpet because of her career and reputation as a comedian — one who was known for her sarcastic humour.
"She was fearless and you really got the sense that she wasn't holding back in her commentary, and that's something that's very rare on TV and, I guess, in life in general," she said.
Growing up, Herrold said she can recall Rivers being the "voice in the background" at red carpet events and the first person that came to mind when it came to that form of coverage — one she helped expose to a wider audience.
"There weren't really many opportunities for people to access that kind of high fashion on a regular basis as they are today," she said.
"The red carpet was one of the only opportunities that people tuning into their TVs had to see these gorgeous gowns from big name designers, and she really brought that to people with her commentary and drawing attention to that as well
Lisa Tant, vice-president, fashion editor at Holt Renfrew, said Rivers helped popularize and create a distinctive red carpet critique.
"There was Mr. Blackwell, but I think Joan put more of a public face on it, said Tant, a reference to the late designer who skewered celebrity fashion crimes on his annual worst-dressed list.
"I think she often said what everyone else was thinking but no one had the courage to say. With her, she was very gutsy and funny, but at the heart of it, I think she always rooted for the underdog, and I believe people knew that."
Despite her often cutting remarks, Tant said she always saw Rivers and her role as simply seeking to entertain.
"I always knew that's what it was for. She wasn't there to beat down people," she said. "She had a very difficult life as well, and I think that was part of her comedy routine, so it was something that I never took seriously. I thought it was fun and not intended to be mean-spirited."
Bergman said that she thought the comedian's fashion-related jibes were "all in good fun."
"If you're a celebrity, you're asking for the good and the bad. Sometimes people can cross the line, but I sort of feel like all's fair in that department," she said. "My only feeling of her was that her style and her critiques were kind of mainstream. ...
"Tilda Swinton, for example, is somebody that the fashion industry loves and people like that that are more avant-garde, Lady Gaga ... that really wasn't her cup of tea which is something I always found interesting about her. A straight-forward beautiful gown is a Joan Rivers thing."
Indeed, Swinton's draped one-sleeved Lanvin creation worn by the star when she took home the best supporting actress prize at the 2008 Oscars landed on Rivers' worst dressed list.
Still, some celebrities who were the brunt of Rivers' jibes seemed to take pride in being the target of her barbs.
"RIP Joan Rivers. Being publicly told that my dress is hideous will never feel quite as awesome. You will be truly missed." tweeted Oscar-nominated actress Anna Kendrick.
"So sad to hear about the great #JoanRivers. I'll never forget how excited I was the first time she made fun of me on TV, I knew I'd made it!" tweeted Canadian supermodel Coco Rocha.
— With files from The Associated Press.
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