In 1930, Joseph and her husband George Waas—described only in newspaper reports as "an American couple"—who were presenting a Coney Island-style attraction in Blackpool under the title of "Josephine-Joseph", were prosecuted in the United Kingdom for false pretences and conspiracy on account of their "Half Woman-Half Man" circus show. Joseph claimed to be 27 years of age at the time (although in reality she was 33–34). The court alleged that the show was a fraud, and that she was not a true hermaphrodite. Waas offered to submit X-rays of Josephine to the magistrates, but refused to submit her to a court doctor's physical examination. The Superintendent in charge of the case admitted that the two sides of Josephine's body looked different, although he had "no idea what the medical testimony may be". The court descriptions of her appearance also match her costume as seen in the film Freaks. She was described as a man on the right side, and a woman on the left, with her right arm longer than her left. Her eyebrows were different. She displayed a bare right leg with a sandal, and a black-stockinged left leg with a woman's shoe. Her hair was brushed from the right side to the left, giving the impression of short hair on the right side. In order to avoid a jury trial, Joseph and Waas pleaded guilty. Waas told the court "I am sorry. I will give up this show and leave the country". Waas, who served as her manager, was fined £25, whilst Josephine was acquitted.

Josephine Joseph is most prominently remembered for a role in the Tod Browning 1932 classic cult film Freaks. Although she only had two lines, she still appeared in a number of scenes, most notably the scene at the wedding reception where she is the one who begins the chant: "We accept her, one of us! We accept her, one of us!". In another notable scene early in the film, "Josephine" gives an alluring look towards the strongman to which another performer responds comically "I think she likes you, but he don't!" She is later seen assembling the rest of the circus freaks for their plan of revenge by saying to them: "Soon, we go".