Who's who in Clemens trial courtroom

Some of the key participants in the Roger Clemens perjury trial that begins this week in Washington, D.C.:

ROGER CLEMENS: Seven-time Cy Young Award winner. Named in MLB's Mitchell report as having used performance-enhancing drugs. Denied before a 2008 congressional hearing that he ever used PEDs, indicted for perjury and obstruction of Congress. Risks prison and his place in the baseball Hall of Fame.

BRIAN McNAMEE: Former close friend of Clemens and personal trainer. Worked as strength coach for Yankees and Blue Jays. The former New York City police officer told federal investigators and former Sen. George Mitchell he injected Clemens and Andy Pettitte with PEDs. Troubled history leaves him vulnerable in cross-examination.

ANDY PETTITTE: Former New York Yankees pitcher with borderline Hall of Fame credentials, named as doper in the Mitchell report. Was close to Clemens for years. Initially said he used HGH once in 2002, then told congressional investigators that he used again in 2004 and that Clemens discussed his own use with him. Seen as key government witness. Rusty Hardin could go after him or portray him as having "misremembered," as Clemens said in hearing.

RUSSELL "RUSTY" HARDIN JR.: Clemens' lead attorney. Legendary Texas litigator, known to charm juries and pull verdicts out of a hat. His cross-examination of Brian McNamee expected to be one of the highlights. Has been a vigorous voice in Clemens' defense, even rising and shouting at House Government Reform committee chairman Henry Waxman during the hearing. Served as Army intelligence officer in Vietnam War.

JUDGE REGGIE WALTON: Tough Pittsburgh-area native who rose to judicial heights. George W. Bush appointee with reputation as judge who will give the defense leeway to try its case, but as one veteran D.C. defense attorney said, "If your client was found guilty, he brought the hammer majorly to bear." Oversaw Scooter Libby and other high-profile cases. Used to tell men accused of domestic violence cautionary tale of woman who put lye on the testicles of a man who abused her.

JEFF NOVITZKY: FDA agent who has spearheaded all the doping investigations that stemmed from the BALCO scandal. Is the agent who found both Kirk Radomski and Brian McNamee. Has been targeted by defense attorneys as overzealous attention-seeker but strategy has never worked. Has repeatedly shown himself to be a solid witness who engages juries.

KIRK RADOMSKI: Former Mets clubhouse attendant who says he supplied PEDs to more than 300 major leaguers. Said he turned over receipt for HGH shipment to Clemens' home to federal investigators.

DANIEL P. BUTLER: Assistant U.S. attorney. Low-key, "meat and potatoes" prosecutor expected to bring a solid case with no flair, but probably lots of timelines. An accomplished para-athlete who uses a wheelchair. Veteran prosecutor of murder and drug cases that required presenting witnesses even more compromised than McNamee to juries.

STEVEN J. DURHAM: Assistant U.S. attorney. Also prosecuted Miguel Tejada. Scouting report from several D.C.-area attorneys: "Very salt of the earth" … "Nickname is 'Bull,' but just because of the movie" … "Kind of person that a jury will trust. Not in there trying to sell you a used car" … "He's the kind of guy you wouldn't mind sitting down having a beer with."

GEORGE J. MITCHELL: Former U.S. Senate majority leader, international peace negotiator and Red Sox fan. Author of MLB's famed Mitchell report on use of performance-enhancing drugs in the sport. May be called to testify, but his report is what spurred congressional interest in Clemens.

T.J. Quinn is a reporter for ESPN's Enterprise/Investigations unit. He can be reached at tjquinn31@yahoo.com.