Officials from the commissioner’s office declined to comment yesterday on any phase of the Mitchell investigation, including which players might be asked to appear. League officials and union officials both said they were unaware of which players had been or would be asked to speak to Mr. Mitchell. A union official said the union, in the past, had received copies of letters Mr. Mitchell sent to former players.  Barry Bonds, the San Francisco Giants slugger who is 13 home runs shy of breaking Hank Aaron’s career record, will most likely not be asked to meet with the panel soon, according to a person briefed on the investigation. Mr. Bonds is under federal investigation over possible perjury during grand-jury testimony in the Bay Area Laboratory Co-Operative case, which involved the distribution of steroids to elite athletes in a wide range of sports.  Mr. Bonds’s lawyer, Michael Rains, said in an interview that Mr. Bonds would decline to speak to the panel if he would risk incriminating himself.  The investigation has left baseball in the uncomfortable position of trying to decide how to celebrate the moment if and when Mr. Bonds breaks Mr. Aaron’s record; it is highly unlikely that the questions surrounding his actions will be resolved by the time that homer is hit.  Mr. Rains said that he still expected Mr. Bonds to receive a letter from Mr. Mitchell “down the road,” because he anticipated that the Mitchell investigation would seek to talk to everyone involved in the Balco case. But he said that Mr. Bonds would cooperate with Mr. Mitchell’s group only if federal prosecutors promised to end the investigation of Mr. Bonds.  “I told my client, there’s not a chance in the world you will make a statement directly to the government, or indirectly, through the Mitchell investigation, unless the federal government gets off your back,” Mr. Rains said in an interview Thursday.  Mr. Mitchell, a Democrat who has headed many investigations since he left the Senate in 1995, is known for his work in seeking a settlement in Northern Ireland and for his Middle East diplomacy under President Bill Clinton. Now a practicing lawyer, he has conducted the investigation quietly over the past year, first seeking background information from former players and others associated with the game, then seeking specific evidence. Only now is he presenting that evidence to the players suspected of being involved.  In responding to inquiries, Mr. Mitchell stepped around questions of whether he was using names provided by Kirk Radomski, a former Mets clubhouse assistant who pleaded guilty last week to selling drugs to major leaguers.  In his plea agreement, Mr. Radomski, of Manorville, N.Y., admitted to distributing steroids, human growth hormone, amphetamines and other drugs to dozens of current and former players in Major League Baseball from 1995 to 2005. As part of that plea, he agreed to cooperate with Mr. Mitchell’s investigation. Mr. Radomski has also handed over at least 36 names of current and former major leaguers to federal prosecutors, according to people familiar with the case.  Matt Parrella, an assistant United States attorney in the Northern District of California who is the lead prosecutor on Mr. Radomski’s case, said that evidence from the Radomski matter would be turned over to the Mitchell investigation on an item-by-item basis. That evidence includes shipping records, financial records, correspondence and contact lists that detailed Mr. Radomski’s drug distribution to players, all seized in a December 2005 raid on Mr. Radomski’s home, according to a statement made last week by United States Attorney Scott N. Schools.  The day before Mr. Radomski pleaded guilty to steroid distribution and money laundering, he testified in front of the grand jury investigating Mr. Bonds, according to court documents filed in a San Francisco court.  Mr. Parrella added that grand jury testimony is secret, and not generally shared with other parties conducting investigations.  Mr. Mitchell declined to say whether the current players he was contacting were the players named by Mr. Radomski. But the timing suggests there may be connections between Mr. Radomski’s plea and the final phase of the Mitchell inquiry, which Mr. Mitchell said would take several months to complete.  “I anticipate issuing a report of my findings and recommendations to the commissioner, and he has agreed that report will be made available to the public,” Mitchell wrote. He said that Mr. Selig would be responsible for making any decisions about punishment of players determined to have used steroids or other performance-enhancing drugs.  The commissioner cannot discipline a player simply for refusing to talk to Mr. Mitchell if that player could incriminate himself. The precedent dates back a quarter-century. In 1980, a pitcher for the Texas Rangers, Ferguson Jenkins, was caught with marijuana, hashish and cocaine at a Toronto airport. When Mr. Jenkins refused to discuss the matter with Bowie Kuhn, then the commissioner, Mr. Kuhn suspended him. An arbitrator overturned that suspension, saying Mr. Jenkins, who faced criminal prosecution, could not be forced into self-incrimination.  But Mr. Selig could discipline a player if he were to conclude there was cause for punishment, which includes any evidence uncovered in the federal investigation. Mr. Selig has already acted in such a case: Federal agents caught Jason Grimsley, a journeyman pitcher, receiving a shipment of human growth hormone last spring. He was subsequently suspended for 50 games, then he retired.  The federal investigators are not likely to prosecute the individual players named by Mr. Radomski because those prosecutors generally go after dealers, not users. Those players still might decline to talk rather than risk incriminating themselves.  As current players are being called to meet with Mr. Mitchell, a battle is beginning in clubhouses across the country over whether Mr. Mitchell will receive the players’ medical records he has requested. So far, the union, the clubs and Mr. Mitchell have not agreed on whether those records will be made available. Medical privacy and employment rules complicate the issue further.  “In the end, it will probably be a watered-down version of the records that comes out,” said one club official involved in the process.  Murray Chass, Jack Curry and Ben Shpigel contributed reporting.  A version of this article appears in print on , on Page A1 of the New York edition with the headline: Baseball’s Steroid Commission Asks Active Players to Appear. Order Reprints| Today's Paper|Subscribe
Three dozen current and former players were being sought, people familiar with an inquiry said, raising the prospect that baseball will be thrown into turmoil.