November 1988Distribution and possession of anabolic steroids becomes a crime in the United States.
June 1991Commissioner Fay Vincent issues a memo adding steroids to baseball's list of banned substances.
August 1998Reporters spy a jar of androstenedione in Mark McGwire's locker during his chase of Roger Maris' single-season home-run record.
April 2001Baseball institutes steroid testing for minor league players.
May 2002In a Sports Illustrated cover story, Ken Caminiti admits he used steroids during his 1996 Most Valuable Player season.
August 2002Baseball announces plans for anonymous "survey" testing of big leaguers.
November 2003Baseball announces that 5 to 7 percent of major leaguers failed survey testing, triggering the creation of a mandatory testing program.
December 2003Ten players, including Barry Bonds, testify before a federal grand jury in connection with the BALCO investigation.
November 2004The 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.
January 2005Baseball and its players union agree to a testing program that will reveal the names of first-time steroid offenders and impose stiffer penalties.
February 2005Former slugger Jose Canseco releases an autobiography, admitting steroid use and leveling allegations at others, including McGwire.
March 2005Six 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.
April 2005Tampa Bay outfielder Alex Sanchez becomes the first major leaguer suspended under the new drug policy.
August 2005Palmeiro's positive test for Stanozolol is announced.
November 2005Players agree to stiffer steroid penalties of 50 games for a first offense, 100 games for a second and a lifetime ban for a third.
March 2006Baseball announces that former Sen. George Mitchell will lead a full investigation of past steroid use in the game.
June 2006The 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.
June 2006Former Oriole David Segui admits using hGH with a doctor's prescription.
October 2006The 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.
September 2007Sports Illustrated reports that Gibbons allegedly received performance enhancers from an Orlando, Fla., pharmacy.
November 2007Bonds, 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.
[FROM STAFF AND WIRE REPORTS]