In 2003, Barry Bonds became embroiled in a scandal when
Greg Anderson of the
Bay Area Laboratory Co-operative (BALCO), Bonds' trainer since 2000, was indicted by a federal
grand jury in the
United States District Court for the Northern District of California and charged with supplying
anabolic steroids to athletes, including a number of baseball players. This led to speculation that Bonds had used performance-enhancing drugs during a time when there was no mandatory testing in Major League Baseball. Bonds declared his innocence, attributing his changed physique and increased power to a strict regimen of bodybuilding, diet and legitimate supplements.
During grand jury testimony on December 4, 2003, Bonds said that he used a clear substance and a cream that he received from his personal strength trainer, Greg Anderson, who told him they were the nutritional supplement flaxseed oil and a rubbing balm for arthritis.
 This testimony was released to the
San Francisco Chronicle by Troy Ellerman, a defense lawyer for
Victor Conte. (Ellerman pleaded guilty to disclosing sealed grand jury testimony on February 14, 2007). Later reports on Bonds’ leaked grand-jury testimony contend that he admitted to unknowingly using "
the clear," a form of the designer steroid
THG and "
the cream", a concoction designed to mask certain hormone ratios helping the user to beat drug tests.
In August 2005, all four defendants in the BALCO steroid scandal trial, including Anderson, struck deals with federal prosecutors that did not require them to reveal names of athletes who may have used banned drugs.