The lawyer hired by Jay-Z to aid rapper 21 Savage in his fight against deportation told NBC News the attention to the case is important to others detained in immigration cases.
Alex Spiro, a New York-based attorney, said Jay-Z hired him with the directive: "get him out and figure out what happened."
On Sunday, 21 Savage, who was born Sha Yaa Bin Abraham-Joseph, was arrested in the Atlanta area by Immigration and Customs Enforcement, which said he is a British national and was in this country illegally.
The 26-year-old musician is being held pending deportation proceedings and if deported, faces a potential 10-year ban from re-entering the country.
ICE said that the rapper was brought to the U.S. as a child legally in 2005, on a visa that expired a year later in July 2006, leaving him without legal status.
"At the end, the attention on the case is important for all the other incarcerated people and that's important to me," Spiro told NBC News. "And it's important to Jay."
Jay-Z, whose real name is Shawn Carter, said the arrest and detention of Abraham-Joseph is "an absolute travesty."
"In addition to being a successful recording artist, 21 deserves to be reunited with his children immediately," Jay-Z said this week in a statement on his official Facebook account.
Spiro said the rapper is being held in "inhumane conditions," but did not offer details.
Abraham-Joseph, who has said he is from Decatur, Georgia, has garnered support since his arrest from big names in hip-hop including Meek Mill, Cardi B and Nicki Minaj, with his detention inspiring the hashtags #free21 and #free21savage.
Spiro said the celebrity support and Abraham-Joseph's star power does not guarantee immigration proceedings will work in his favor.
"Everyone's instinct is that it makes it easier and that they have more help and more resources," Spiro said. "But the truth is, the government uses more resources and gets more dug in. So it's nuanced."
Abraham-Joseph is nominated for two awards at Sunday's Grammy Awards, including record of the year for the song "Rockstar."