Sefolosha was injured in the early-morning hours Wednesday outside a Manhattan night club, where a police report states he was resisting arrest. Sefolosha and Hawks teammate Pero Antic were arrested on suspicion of interfering with the efforts of local police to set up a crime scene after the stabbing of Indiana Pacers forward Chris Copeland.
"The players' union is concerned about the circumstances of Thabo Sefolosha and Pero Antic's arrest and is doing its own investigation of the situation," NBPA spokeswoman Tara Greco said. "The union was fully engaged in supporting all three players in court and in the precinct this week, and will continue to stay engaged as each situation evolves."
The police are facing new questions about their tactics during the incident, as Sefolosha suffered a season-ending broken fibula, which went untreated overnight and into Wednesday as Sefolosha languished in custody.
A New York Police Department spokesman said that the NYDP's Internal Affairs Bureau is reviewing the "entire incident" surrounding the arrests of Sefolosha and Antic. The spokesman said a review takes place whenever someone claims they were injured during an arrest.
On Thursday evening, TMZ published a video that it says shows five officers surrounding Sefolosha at the scene and trying to take hold of him. TMZ says the video shows one officer grabbing Sefolosha by the back of the neck before bringing him down to the ground.
Sefolosha has hired noted criminal defense attorney Alex Spiro, who told TMZ the video "speaks for itself."
On Friday night, TMZ published a second video, shot by a witness, that shows six officers tugging at Sefolosha, including one who swung his baton.
Antic also expressed support for Sefolosha.
"There's a video out that speaks for itself," Antic said Friday. "The only thing I can say is that we feel bad for the bad publicity that we brought to the Hawks organization and the Hawks family."
Antic said that the incident was "a pure example of being at the wrong place at the wrong time. People have known Thabo for so many years in the league. Thabo is one of the greatest guys." Antic added that he and Sefolosha had no knowledge or involvement in the attack on Copeland.
"We don't have nothing to do with what happened with that. We weren't together," Antic said. "We didn't see the guy, and whatever happened, happened way before."
Sources close to the situation say the players' association has been very active, as well. Sources say that representatives from the players' association appeared Thursdayat the 10th Precinct in Manhattan with several inquiries into the incident.
The head of the players' association, Michele Roberts, came to the NBPA after decades as a respected lawyer. She began her career as a public defender.
Privately, sources say, Hawks officials also have begun to raise questions about the specific circumstances that led to Sefolosha being held by police for several hours with a broken fibula.
ESPNNewYork.com's Ian Begley contributed to this report.
Players' association investigating Sefolosha arrest
ESPN legal analyst Roger Cossack discusses the National Basketball Players Association's investigation into the arrest of Thabo Sefolosha.