Thomas Bach, the president of the International Olympic Committee, said on Wednesday that Russian sports federations could be kept out of the Summer Olympics if allegations about a state-sponsored cover-up of doping among Russian athletes were proved true.  “We will apply our zero tolerance policy, not only with regard to the athletes but also with regard to everybody implicated and within our reach,” Mr. Bach said on a call with the news media on Wednesday.  In an op-ed piece in USA Today, he cited the “shocking new dimension in doping” and the “unprecedented level of criminality” of which Russia had been accused.  Mr. Bach declined to say if the Russian Federation as a whole could be kept from competition, indicating that the I.O.C. would wait until the World Anti-Doping Agency had completed an investigation into conduct at the Olympic testing laboratory at the 2014 Sochi Games.  That investigation is seeking to verify the account of Grigory Rodchenkov, Russia’s former antidoping lab director, who oversaw the Sochi lab. He told The New York Times that during Sochi he had worked at the direction of the Russian government, expunging the tainted urine of Russian athletes who were using performance-enhancing drugs. He said that with the help of the Russian intelligence service, he had gained access to supposedly tamper-proof drug sample bottles and had surreptitiously substituted in athletes’ clean urine.  Mr. Bach said the I.O.C. had no control over whether WADA’s investigation would be completed before the Summer Olympics in Rio de Janeiro, which start on Aug. 5. “This is in the hands of WADA,” he said, adding that he urged anyone with further information on the Sochi lab operation and Dr. Rodchenkov’s allegations to call an integrity and compliance hotline.  Dr. Rodchenkov’s account cast suspicion on not just the Russian athletes who competed in Sochi but those who competed at recent Summer Games, namely those in Beijing in 2008 and London in 2012.  According to Dr. Rodchenkov, director of the Moscow antidoping lab from 2005 to 2015, Russian athletes were doping in advance of Beijing and London. Before London, he said, he developed a three-drug cocktail of anabolic steroids that helped speed athletes’ recovery from grueling training regimens. Mixed with liquor, that concoction, he said, drastically decreased the drugs’ detection window, allowing athletes to dope days before competition.  On Tuesday, the I.O.C. announced that it had retested the doping samples of athletes who competed in Beijing, discovering 31 athletes from six sports and 12 countries with suspicious test results that could keep them from the Rio Games. Officials did not specify if Russia was included and said that further retesting of medalists’ samples from the London Games was planned and would be completed before the 2016 Olympics.  Separate from the I.O.C.’s announcement, the Russian Weightlifting Federation announced on Tuesday that four Russian lifters, among them a world-record holder, had been suspended for doping.  Dr. Rodchenkov said in interviews with The Times this month that weight lifting was the sport most ridden with drug abuse. “You cannot get Olympic medals in weight lifting without system of doping,” he said.  In a statement released Tuesday, WADA’s president, Craig Reedie, said the organization would publish a report upon completion of its investigation.  Once that inquiry is complete, Mr. Bach said, the I.O.C. may explore lifetime bans on athletes, coaches and others. He added that financial penalties and suspensions were also possible.  The Times reported on Tuesday that the United States Justice Department was investigating state-sponsored doping in Russia, scrutinizing Russian government officials, athletes, coaches and antidoping authorities. Among the people federal prosecutors are focused on is Dr. Rodchenkov, who fled to the United States last fall with one change of clothes and the laptop he had used at Sochi.  Mr. Bach declined to comment on the Justice Department’s criminal inquiry, conducted by the United States attorney’s office for the Eastern District of New York, in Brooklyn.  “We have no information,” Mr. Bach said of the Justice Department investigation. “I don’t know about any legal grounds for this.”  A version of this article appears in print on May 19, 2016, on page B15 of the New York edition with the headline: Russians Could Be Barred, I.O.C. Head Says. Order Reprints| Today's Paper|Subscribe
Thomas Bach said on Wednesday that the accusations of state-run doping in Russia, if proven, could lead to suspensions of sports federations, fines and lifetime bans.