Calabasas lawyer Mac Nehoray declined to state the purpose of the recording, but said it was "by mutual agreement."
"My client is devastated that this got out," he said, adding that he and Stiviano "have an idea" who released it. He declined to identify that person.
"Someone released it for money," he said.
Stiviano recorded the rants that led to Sterling's banishment from professional basketball and said through her attorney that she was never his mistress.
Contrary to some media reports, Stiviano was not in a romantic relationship with Sterling, her attorney said.
"It's nothing like it's been portrayed," Nehoray said. "She's not the type of person everyone says."
Stiviano stepped outside her home several times Tuesday and always had her face covered with a tinted visor. The media hounded her with questions but she refused to answer until the remark about being president.
Stiviano often sat courtside with Sterling at Clippers games and is still reeling from the release of the recording in which he chastises her for associating with African Americans, including Magic Johnson, her attorney said.
She recorded the conversation, Nehoray said, but had no role in providing the damaging tape to TMZ, the website that first broke the story. The conversation occurred at her home in September in the presence of another person and Sterling knew he was being recorded, Nehoray added.
He also said Stiviano and the 80-year-old Clippers owner never had a sexual or romantic relationship and that descriptions of her as his mistress in the media and in a lawsuit filed by Sterling's wife were erroneous.
Rochelle Sterling, who has been married to Donald Sterling for more than 50 years, filed suit against Stiviano in March in an effort to reclaim a $1.8-million apartment, luxury autos and cash he gave her.
The suit asserts that Stiviano instigated a sexual relationship with the Beverly Hills billionaire after they met at the 2010 Super Bowl. He was the latest in a string of rich men she had seduced, the suit contends.
Nehoray said those claims were false.
"She had no association with any rich people before this," he said.
Nehoray said Sterling's wife was friendly with Stiviano and was aware he had purchased an apartment for her.
Rochelle Sterling's attorneys did not return calls and emails requesting comment.
Sterling was banned for life Tuesday by the NBA for the remarks attributed to him in the recording.
With paparazzi tracking her every move, V. Stiviano roller-skated in her driveway Tuesday and said she wanted to be president.
“One day, I will become president of the United States of America and I will change the legislation and laws,” Stiviano said in one of several odd encounters with media camped outside her home. “Modern day history. Civil rights movement.”