Distribution and possession of anabolic steroids becomes a crime in the United States.
Commissioner Fay Vincent issues a memo adding steroids to baseball's list of banned substances.
Reporters spy a jar of androstenedione in Mark McGwire's locker during his chase of Roger Maris' single-season home-run record.
Baseball institutes steroid testing for minor league players.
In a Sports Illustrated cover story, Ken Caminiti admits he used steroids during his 1996 Most Valuable Player season.
Baseball announces plans for anonymous "survey" testing of big leaguers.
Baseball announces that 5 to 7 percent of major leaguers failed survey testing, triggering the creation of a mandatory testing program.
Ten players, including Barry Bonds, testify before a federal grand jury in connection with the BALCO investigation.
The San Francisco Chronicle obtains leaked testimony in which Jason Giambi admits using steroids and Bonds says he allowed his trainer to apply a cream that he thought was flaxseed oil.
Baseball and its players union agree to a testing program that will reveal the names of first-time steroid offenders and impose stiffer penalties.
Former slugger Jose Canseco releases an autobiography, admitting steroid use and leveling allegations at others, including McGwire.
Six active and former players testify before a Congressional panel investigating steroid use in baseball. McGwire says he doesn't want to discuss the past. Orioles first baseman Rafael Palmeiro issues a finger-wagging denial of steroid use.
Tampa Bay outfielder Alex Sanchez becomes the first major leaguer suspended under the new drug policy.
Palmeiro's positive test for Stanozolol is announced.
Players agree to stiffer steroid penalties of 50 games for a first offense, 100 games for a second and a lifetime ban for a third.
Baseball announces that former Sen. George Mitchell will lead a full investigation of past steroid use in the game.
The home of former Orioles reliever Jason Grimsley is raided by federal agents. Grimsley admits to using hGH and allegedly shares names of other drug users.
Former Oriole David Segui admits using hGH with a doctor's prescription.
The Los Angeles Times reports that the Orioles' , and are among the players named in Grimsley's affidavit. The facts of the story are disputed by an attorney involved with the case.
Sports Illustrated reports that Gibbons allegedly received performance enhancers from an Orlando, Fla., pharmacy.
Bonds, the new home run king, is indicted on federal perjury charges for allegedly lying about steroid use.
• On Dec. 6, outfielders and Jose Guillen, linked in reports to receiving hGH, are suspended for the first 15 days of the 2008 season.
• On Dec. 7, Bonds pleads not guilty to four counts of perjury and one of obstruction of justice.
• Yesterday, the Mitchell Report is released, naming 87 players linked to performance-enhancing drugs, including seven MVPs and 31 All-Stars.