Major League Baseball players and owners are opposing subpoenas to appear before a U.S. Congressional committee investigating the use of steroids in the sport.

Baseball has sent a letter to the committee, saying it had overstepped its legal bounds. Angry baseball officials accused the government of meddling and ignoring recent progress. Major League Baseball has started testing players this season for steroids. But lawmakers want to know if the new screening policy will be effective and perhaps if new drug and labor laws should be considered.

Home run sluggers Mark McGwire, Sammy Sosa, Jason Giambi, as well as Jose Canseco, the author of a best-selling book about the abuse of steroids, were subpoenaed Wednesday to testify at a House Government Reform Committee hearing on March 17.

Subpoenas were also issued to Curt Schilling, Rafael Palmeiro and Frank Thomas along with players' union chief Donald Fehr and baseball vice presidents Rob Manfred and Sandy Alderson.