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Felecia Redd always communicates more than the words she hears when interpreting in sign language. She enlarges and dramatizes her gestures when conveying the soaring rhetoric of a black preacher. She shifts her facial expressions to reflect a speaker’s emotions and vocal styles.

“I try to match them,” said Redd, a sign language interpreter for 19 years.

Redd, who is black but was taught to sign by white teachers, said she did what came naturally, not thinking about the racial aspect of her signing.

A 30-minute documentary changed that. “Signing Black in America” describes how a distinctive black signing system, or Black ASL, has evolved, reflecting the historic isolation of members of the black deaf community and their contemporary sense of solidarity.

The signs are often larger, involving two hands when white signers use one, and gestured closer to the forehead than the chin. Some words are represented by completely different signs.

“I did it. But I didn’t know it was a thing, that it was Black ASL,” said Redd, explaining how moved she was to understand the system’s enduring cultural importance for users who are marginalized by both race and hearing loss.

“I’m always told by deaf African Americans, ‘I am black first; then I’m deaf,’” Redd said. “White deaf people are deaf first and then white.”

The new film is the 14th in a series produced by North Carolina State University’s Language & Life Project, which celebrates the linguistic diversity of the United States and examines how people use language to define themselves. “First Language” documents the Eastern Band of Cherokee’s attempts to save their mother tongue; “Mountain Talk” records the songs and stories of Southern Appalachia; and “Speaking Black in America,” which won a Midsouth Regional Emmy Award this week in the documentary/cultural category, traces how a history of segregation and the contemporary sense of shared identity shape the ways African Americans communicate.

The project also has deeper sociolinguistic goals that are key for users of Black ASL — to investigate why people often “code switch,” changing the way they speak when they move from one social setting to another, and why one form of a language is sometimes considered “better” than another.

Those questions prompted lively interaction among students, teachers and interpreters who gathered last week at D.C.’s Gallaudet University to watch the film and discuss it with a panel that included several people who were featured.

Sign language, like spoken language, has regional variations (people sign more slowly in the South, for example), as well as features that reflect gender, age, socioeconomic status and, it turns out, race.

A history of educational and social segregation set black signers apart in the 1860s, when schools opened for them, leading to the development of separate grammatical features and vocabulary, in much the way that spoken black English (known as African American English or AAE by linguists) is distinct.

Carolyn McCaskill, a professor in Gallaudet’s Department of ASL and Deaf Studies, who grew up signing at the Alabama School for the Negro Deaf and Blind, spotted differences 50 years ago that went way beyond the size and style of signing.

At 15, McCaskill transferred to an integrated school, where she saw white students using one hand rather than two to convey terms such as “why” and “don’t know” and employing entirely different signs for everyday words such as “pregnant,” “boss,” “flirt” and “school.” McCaskill began to imitate them.

When she went home, she switched again to reassimilate to her own black culture, recalled McCaskill, who was on the panel.

McCaskill’s code-switching remains a common experience for deaf black students, who often change to accommodate whites, according to Solimar Aponte-Huertas, a deaf student from Puerto Rico.

“It’s kind of sad,” she said through an interpreter, adding that there is a common belief that “black signing isn’t as good.”

Still, there is rising pride in the dynamism and almost dance-like style of Black ASL at Gallaudet, where about 13 percent of the students are black.

“It’s just beautiful,” said Candas Barnes, an African American interpreter, describing how body language derived from hip-hop and other aspects of contemporary black culture have infused the signing.

“It’s not so hidden anymore,” said Ceil Lucas, a retired professor of linguistics, who, with McCaskill, was part of a team of researchers who formally described the structure of black sign language in their 2011 book, “The Hidden Treasure of Black ASL."

On-screen, Warren “WaWa” Snipe, a deaf writer and performer, sums up the significance of a signing style that reflects who he is.

“That’s my culture,” says Snipe, who graduated from Gallaudet in 1994. “That’s a sense of identity. That’s where I belong.”

Still, the bigger, more expressive gestures associated with Black ASL can cause confusion. Franklin Jones, an African American lecturer in the Department of ASL and Deaf Studies, said his signing sometimes made white students think he was angry.

“I had to explain,” he said.

“White people say it’s ‘attitude,’ but it’s just their style,” said Aponte-Huertas.

Navigating that style can be a challenge for nonblack interpreters.

A new documentary looks at how historic segregation and a sense of shared identity have led to the development of a separate form of sign language. (The Language & Life Project, NC State University)

Naveh Berner-Kadish, who is majoring in interpretation, looked for guidance from the panel: How should he, a white, Jewish man, interpret for people whose background and culture he does not share?

There are simply some assignments a white interpreter should not take, the panelists said, burdened as the interaction is with the implications of a white person speaking for a black person, as well as the potential for cultural appropriation. In other cases, it might make sense to work with a black interpreter to avoid those pitfalls. Taking the time to learn about the linguistic and cultural differences is key, they agreed.

“It’s a fine line, giving the linguistic and meta-linguistic features without crossing the line over to appropriating that style,” Berner-Kadish said later. “I would have to make sure I was very much in tune with the community.”

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