Lena Dunham has supported the Free the Nipple campaign by sharing a topless photo of herself - with her nipples covered.
Free the Nipple is a US campaign to change laws around breastfeeding in public and female toplessness.
In the picture, posted on Instagram ahead of her appearance at the Golden Globes, Lena has nipple shields on.
The social networking site has a "no nudity" policy, which the star seems to have got around by wearing pasties.
Girls producer Jenny Konner took the picture and later shared another photograph of Lena at the award ceremony with the pasties stuck to her face.
The star often appears topless in Girls, the HBO series created and written by Dunham.
According to Free the Nipple, it is "effectively illegal" for a woman to be topless or breast feed in public in 35 US states.
"In less tolerant places like Louisiana, an exposed nipple can take a woman to jail for up to three years," the campaign claims.
Protestors have marched through the streets of New York with bare breasts as part of their "mission to empower women".
Bruce Willis' daughter Scout staged a topless protest in New York last May over Instagram's removal of a picture featuring women's nipples.
In a series of tweets, she used the hashtag #FreeTheNipple to protest at the website's anti-nudity policy.