Team Sky rider Chris Froome of Britain wears the race leader's yellow jersey as he speeds downhill during the 110.5-km (68.6 miles) 20th stage of the 102nd Tour de France cycling race from Modane to Alpe d'Huez in the French Alps mountains, France, in this picture taken July 25, 2015. British cyclist Chris Froome said December 4, 2015 that tests he took after winning the Tour de France proved that he does not use performance-enhancing drugs. During this year's race, Froome was accused of doping by former riders, reporters and fans of a race that has been beset by doping scandals for almost 20 years. Picture taken July 25, 2015. REUTERS/Stefano Rellandini/Files
Picture Supplied by Action Images 

Team Sky rider Chris Froome of Britain, the race overall leader's yellow jersey, waits for the start of the 110.5-km (68.6 miles) 20th stage of the 102nd Tour de France cycling race from Modane to Alpe d'Huez in the French Alps mountains, France, in this picture taken July 25, 2015. British cyclist Chris Froome said December 4, 2015 that tests he took after winning the Tour de France proved that he does not use performance-enhancing drugs. During this year's race, Froome was accused of doping by former riders, reporters and fans of a race that has been beset by doping scandals for almost 20 years. Picture taken July 25, 2015. REUTERS/Stefano Rellandini/Files
Picture Supplied by Action Images 

Former strength and conditioning coach Brian McNamee speaks with his lawyer outside the Brooklyn Federal Courthouse in the Brooklyn Borough of New York April 29, 2014. McNamee, who claims to have helped acquire performance-enhancing drugs for Major League Baseball players he personally trained, was in court as part of a defamation case brought against him by Roger Clemens. REUTERS/Brendan McDermid (UNITED STATES - Tags: SPORT BASEBALL CRIME LAW) 

Former strength and conditioning coach Brian McNamee exits the Brooklyn Federal Courthouse in the Brooklyn Borough of New York April 29, 2014. McNamee, who claims to have helped acquire performance-enhancing drugs for Major League Baseball players he personally trained, was in court as part of a defamation case brought against him by Roger Clemens. REUTERS/Brendan McDermid (UNITED STATES - Tags: SPORT BASEBALL CRIME LAW) 

Former Major League pitcher Roger Clemens exits the Brooklyn Federal Courthouse in the Brooklyn Borough of New York April 29, 2014. Clemens was in court as part of a defamation case against his former former strength and conditioning coach Brian McNamee, who claims to have helped acquire performance-enhancing drugs for Major League Baseball players he personally trained. REUTERS/Brendan McDermid (UNITED STATES - Tags: SPORT BASEBALL CRIME LAW) 

Former Major League pitcher Roger Clemens exits the Brooklyn Federal Courthouse in the Brooklyn Borough of New York April 29, 2014. Clemens was in court as part of a defamation case against his former former strength and conditioning coach Brian McNamee, who claims to have helped acquire performance-enhancing drugs for Major League Baseball players he personally trained. REUTERS/Brendan McDermid (UNITED STATES - Tags: SPORT BASEBALL CRIME LAW) 

Former Major League pitcher Roger Clemens (R) exits the Brooklyn Federal Courthouse in the Brooklyn Borough of New York April 29, 2014. Clemens was in court as part of a defamation case against his former former strength and conditioning coach Brian McNamee, who claims to have helped acquire performance-enhancing drugs for Major League Baseball players he personally trained. REUTERS/Brendan McDermid (UNITED STATES - Tags: SPORT BASEBALL CRIME LAW) 

Former Major League pitcher Roger Clemens (R) poses with a fan as he exits the Brooklyn Federal Courthouse in the Brooklyn Borough of New York April 29, 2014. Clemens was in court as part of a defamation case against his former former strength and conditioning coach Brian McNamee, who claims to have helped acquire performance-enhancing drugs for Major League Baseball players he personally trained. REUTERS/Brendan McDermid (UNITED STATES - Tags: SPORT BASEBALL CRIME LAW) 

Former strength and conditioning coach Brian McNamee exits the Brooklyn Federal Courthouse in the Brooklyn Borough of New York April 29, 2014. McNamee, who claims to have helped acquire performance-enhancing drugs for Major League Baseball players he personally trained, was in court as part of a defamation case brought against him by Roger Clemens. REUTERS/Brendan McDermid (UNITED STATES - Tags: SPORT BASEBALL CRIME LAW) 

Former Major League pitcher Roger Clemens exits the Brooklyn Federal Courthouse in the Brooklyn Borough of New York April 29, 2014. Clemens was in court as part of a defamation case against his former former strength and conditioning coach Brian McNamee, who claims to have helped acquire performance-enhancing drugs for Major League Baseball players he personally trained. REUTERS/Brendan McDermid (UNITED STATES - Tags: SPORT BASEBALL CRIME LAW) 

Former strength and conditioning coach Brian McNamee exits the Brooklyn Federal Courthouse in the Brooklyn Borough of New York April 29, 2014. McNamee, who claims to have helped acquire performance-enhancing drugs for Major League Baseball players he personally trained, was in court as part of a defamation case brought against him by Roger Clemens. REUTERS/Brendan McDermid (UNITED STATES - Tags: SPORT BASEBALL CRIME LAW) 

Former Major League Baseball player Jose Canseco reacts to a question during a round table discussion regarding the prevalence of performance-enhancing drugs in sports, in New York September 4, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: SPORT BASEBALL HEALTH DRUGS SOCIETY) 

Former Major League Baseball player Jose Canseco speaks during a round table discussion regarding the prevalence of performance-enhancing drugs in sports, in New York September 4, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: SPORT BASEBALL HEALTH DRUGS SOCIETY) 

Former Major League Baseball player Jose Canseco speaks during a round table discussion regarding the prevalence of performance-enhancing drugs in sports, in New York September 4, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: SPORT BASEBALL HEALTH DRUGS SOCIETY) 

Former Canadian Olympian Ben Johnson speaks during a round table discussion regarding the prevalence of performance-enhancing drugs in sports, in New York September 4, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: SPORT HEADSHOT ATHLETICS HEALTH DRUGS SOCIETY) 

Former Canadian Olympian Ben Johnson speaks during a round table discussion regarding the prevalence of performance-enhancing drugs in sports, in New York September 4, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: SPORT PROFILE HEADSHOT ATHLETICS HEALTH DRUGS SOCIETY) 

Former Major League Baseball player Jose Canseco speaks next to former Canadian Olympian Ben Johnson (2nd R) during a round table discussion regarding the prevalence of performance-enhancing drugs in sports, in New York September 4, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: SPORT DRUGS SOCIETY HEALTH BASEBALL ATHLETICS) 

Australian entrepreneur Jaimie Fuller (R) speaks next to former Major League Baseball player Jose Canseco (L) and former Canadian Olympian Ben Johnson during a round table discussion regarding the prevalence of performance-enhancing drugs in sports, in New York September 4, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: SPORT ATHLETICS BASEBALL DRUGS SOCIETY HEALTH BUSINESS) 

Former Major League Baseball star Jose Canseco (L) and Australian entrepreneur Jaimie Fuller (R) listen to former Canadian Olympian Ben Johnson speak during a round table discussion regarding the prevalence of performance enhancing drugs in sports in New York, September 4, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: SPORT BASEBALL DRUGS SOCIETY BUSINESS) 

Former Major League Baseball star Jose Canseco speaks during a round table discussion regarding the prevalence of performance enhancing drugs in sports in New York, September 4, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: SPORT BASEBALL) 

A fan holds a sign that reads "MVP of P.E.D.'s", an acronym of "Performing Enhancing Drugs", as New York Yankees Alex Rodriguez comes to bat against the Toronto Blue Jays during the eighth inning of their MLB American League baseball game in Toronto, August 26, 2013. REUTERS/Mark Blinch (CANADA - Tags: SPORT BASEBALL) 

A statue of a horse head is seen in Newmarket, eastern England April 23, 2013. A trainer for Sheikh Mohammed bin Rashid Al Maktoum's horses has admitted to a "catastrophic error" in using banned steroids to dope horses at the Dubai ruler's Godolphin racing stable. Eleven horses tested positive for steroids, including stanozolol - the performance-enhancing drug used by disgraced Olympic sprinter Ben Johnson at the 1988 Seoul Olympics. REUTERS/Stefan Wermuth (BRITAIN - Tags: SPORT HORSE RACING) 

A road sign warning motorists of the presence of horse is seen in Newmarket, eastern England April 23, 2013. A trainer for Sheikh Mohammed bin Rashid Al Maktoum's horses has admitted to a "catastrophic error" in using banned steroids to dope horses at the Dubai ruler's Godolphin racing stable. Eleven horses tested positive for steroids, including stanozolol - the performance-enhancing drug used by disgraced Olympic sprinter Ben Johnson at the 1988 Seoul Olympics. REUTERS/Stefan Wermuth (BRITAIN - Tags: SPORT HORSE RACING) 

A statue of a horse is silhouetted against the sky near Newmarket, eastern England April 23, 2013. A trainer for Sheikh Mohammed bin Rashid Al Maktoum's horses has admitted to a "catastrophic error" in using banned steroids to dope horses at the Dubai ruler's Godolphin racing stable. Eleven horses tested positive for steroids, including stanozolol - the performance-enhancing drug used by disgraced Olympic sprinter Ben Johnson at the 1988 Seoul Olympics. REUTERS/Stefan Wermuth (BRITAIN - Tags: SPORT HORSE RACING) 

The entrance of Godolphin stables is seen in Newmarket, eastern England April 23, 2013. A trainer for Sheikh Mohammed bin Rashid Al Maktoum's horses has admitted to a "catastrophic error" in using banned steroids to dope horses at the Dubai ruler's Godolphin racing stable. Eleven horses tested positive for steroids, including stanozolol - the performance-enhancing drug used by disgraced Olympic sprinter Ben Johnson at the 1988 Seoul Olympics. REUTERS/Stefan Wermuth (BRITAIN - Tags: SPORT HORSE RACING) 

A sign is seen at the entrance of Godolphin stables in Newmarket, eastern England April 23, 2013. A trainer for Sheikh Mohammed bin Rashid Al Maktoum's horses has admitted to a "catastrophic error" in using banned steroids to dope horses at the Dubai ruler's Godolphin racing stable. Eleven horses tested positive for steroids, including stanozolol - the performance-enhancing drug used by disgraced Olympic sprinter Ben Johnson at the 1988 Seoul Olympics. REUTERS/Stefan Wermuth (BRITAIN - Tags: SPORT HORSE RACING) 

CYCLING-ARMSTRONG/ - Timeline of Lance Armstrong's career and the USADA doping charges, with facts on performance-enhancing drugs Armstrong confessed using in each of his seven Tour wins, during his interview with Oprah Winfrey. (SIN06) 

OLY-DOPING2/ - Graphic listing effects of performance-enhancing drugs to athletes. Includes procedures of doping controls at the Olympics. RNGS. Colour graphic only. (SIN09) 

Chinese Olympic swimmer Ye Shiwen is seen posing after a local competition in a picture from a family album in Hangzhou August 2, 2012. At the Chen Jinglun Sports school in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

Chinese Olympic swimmer Ye Shiwen is seen playing in a park in a picture from a family album in Hangzhou August 2, 2012. At the Chen Jinglun Sports School in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA) 

In this picture from a family album, Chinese Olympic swimmer Ye Shiwen celebrates after a competition, in Hangzhou August 2, 2012. At the Chen Jinglun Sports School in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

A girl waits outside the Chen Jinglun Sports School Natatorium in Hangzhou August 2, 2012, where Chinese Olympic swimmer Ye Shiwen trained when she was young. At the Chen Jinglun Sports School in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

In this picture from a family album, Chinese Olympic swimmer Ye Shiwen, aged nine, poses with medals from a local competition, in Hangzhou August 2, 2012. At the Chen Jinglun Sports School in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

Ye Qingsong, father of Chinese Olympic swimmer Ye Shiwen, stands inside his house in Hangzhou, August 2, 2012. At the Chen Jinglun Sports school in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

Kids swim during training at Hangzhou Chen Jinglun Sports School Natatorium in Hangzhou August 2, 2012, where Chinese Olympic swimmer Ye Shiwen trained when she was young. At the Chen Jinglun Sports School in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

A girl waits outside the Chen Jinglun Sport School Natatorium in Hangzhou August 2, 2012, where Chinese Olympic swimmer Ye Shiwen trained when she was young. At the Chen Jinglun Sports School in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

In this picture from a family album, Chinese Olympic swimmer Ye Shiwen poses with a gold medal next to an unidentified friend after a competition, in Hangzhou August 2, 2012. At the Chen Jinglun Sports School in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

Ye Qingsong, father of Chinese Olympic swimmer Ye Shiwen, shows some of his daughter's gold medals during an interview with Reuters in Hangzhou August 2, 2012. At the Chen Jinglun Sports School in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

In this picture from a family album, Chinese Olympic swimmer Ye Shiwen, aged nine, poses with medals from a local competition, in Hangzhou August 2, 2012. At the Chen Jinglun Sports School in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

Parents wait for their children at the Chen Jinglun Sports School Natatorium in Hangzhou August 2, 2012, where Chinese Olympic swimmer Ye Shiwen also trained when she was young. At the Chen Jinglun Sports school in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week. But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

A girl swims during a training session at Hangzhou Chen Jinglun Sport school Natatorium, where Chinese Olympic swimmer Ye Shiwen also trained, in Hangzhou, August 2, 2012. At the Chen Jinglun Sports school in the picturesque city of Hangzhou, the slogan "Today's sports school student, tomorrow's Olympics stars" greeted all those who entered, and it was prescient greeting that proved true for one little girl, Olympics swimming sensation Ye Shiwen. At 16, Ye's powerful strokes and rapid laps won her gold in the 200 metres individual medley and the 400 medley in London this week; But as she shattered world records and smiled for the cameras, her swift timings led some to speculate, without proof, that she might be taking performance enhancing drugs. But at the pool where Ye got her first dip at 6 years old, Ye's childhood coach Wei Wei said her success is boiled down to good genes and prodigious hard work. REUTERS/Carlos Barria (CHINA - Tags: SPORT OLYMPICS SWIMMING) 

Former baseball star Roger Clemens (2nd R) stands with his family outside the Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW TPX IMAGES OF THE DAY) 

Former baseball star Roger Clemens speaks outside Federal District Court in Washington June 18, 2012. At right is his attorney Rusty Hardin. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Former baseball star Roger Clemens speaks outside Federal District Court in Washington June 18, 2012. At right is his attorney Rusty Hardin. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Former baseball star Roger Clemens (2nd R) stands with his family outside the Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Former baseball star Roger Clemens stands with his family as his lawyers speak outside Federal District Court in Washington June 18, 2012. At the microphone stand is attorney Rusty Hardin. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Former baseball star Roger Clemens (R) stands with his family before the media outside Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Former baseball star Roger Clemens becomes emotional as he talks to reporters outside Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW HEADSHOT) 

Former baseball star Roger Clemens becomes emotional as he talks to reporters outside Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW HEADSHOT) 

Former baseball star Roger Clemens reacts as he talks to reporters outside Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW HEADSHOT) 

Former baseball star Roger Clemens (C) looks toward his attorney Rusty Hardin (R) as they depart the Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Former baseball star Roger Clemens (L) looks toward his attorney Rusty Hardin (R) as they depart the Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Attorney Rusty Hardin gestures toward former baseball star Roger Clemens as they speak to reporters outside the Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Former baseball star Roger Clemens (2nd R) stands with his family outside the Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Former baseball star Roger Clemens (C) walks with his son Kacy (R) and wife Debbie (front) as he leaves Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Former baseball star Roger Clemens (C) walks with his wife Debbie (L) as he leaves Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Former baseball star Roger Clemens talks to reporters outside Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS CRIME LAW) 

Former baseball star Roger Clemens reacts as he talks to reporters outside Federal District Court in Washington June 18, 2012. A jury on Monday acquitted Clemens of all six criminal charges against him in a trial to decide whether he lied to Congress about using performance-enhancing drugs. REUTERS/Kevin Lamarque (UNITED STATES - Tags: POLITICS HEADSHOT CRIME LAW)