A few bad apples are trying to ruin baseball's reputation and sully America's national pastime, several Major League Baseball (search) players said Thursday as they testified before a congressional panel investigating steroid abuse.

On a day of extraordinary theater, House Government Reform Committee members professed their love of baseball before attacking the sport's new drug policy and warning Congress could get involved if stronger steps aren't taken. Major League Baseball Commissioner Bud Selig (search) watched from a few feet away, waiting more than eight hours for his chance to respond.

Most of the players said they believe only a very small minority of ballplayers are using steroids, and they added that they want it on the record that they have never used the performance-enhancing drugs themselves.

But one player stood out among the six players who testified. Mark McGwire, who thrilled the nation when he shattered Roger Maris' cherished single-year home run record in 1998, stonewalled throughout most of his testimony. Big Mac promised to do everything he could to rid the game of performance-enhancing drugs and to encourage kids not to use them, but repeatedly said that he did not want to talk about the past and refused to deny that he ever used steroids.

Asked by Rep. Elijah Cummings, D-Md., whether he was asserting his Fifth Amendment right not to incriminate himself, McGwire said: "I'm not here to talk about the past. I'm here to be positive about this subject."

Asked whether use of steroids was cheating, McGwire said: "That's not for me to determine."

The other ballplayers were not nearly as evasive.

"Everything I heard about steroids and human growth hormones is that they are very bad for you and very lethal. I would never put anything that dangerous in my body," Baltimore Oriole Sammy Sosa (search) said through his attorney, who read the player's statement.

"To be clear — I have never taken illegal performance-enhancing drugs ... I have not broken the laws of the United States or the laws of the Dominican Republic," he added, saying he supports the testing of professional athletes.

The six baseball players who appeared before the committee — Chicago White Sox slugger Frank Thomas (search) testified via satellite — were asked to help shine some light on the league's new drug-testing policy.

The group included three of the top 10 home run hitters in major league history — former Oakland and St. Louis star McGwire, Sosa and Baltimore Oriole Rafael Palmeiro (search). McGwire and Sosa were widely credited with boosting baseball's popularity in 1998 when they battled to break Roger Maris' season record of 61 homers. McGwire finished with 70 home runs that year, and Sosa hit 66.

McGwire said: "There's been a problem with steroid use in baseball," but he added he would not help point the finger at those players and friends who have used such substances.

"I will do everything in my power to help the game, its players and fans," McGwire said, choking back tears. "My heart goes out to every parent whose son or daughter were victims of steroid use ... I hope that these hearings can prevent other families from suffering."

Palmeiro added: "I have never used steroids. Period. I don't know how to say it any more clearly than that. Never."

Thomas said Major League Baseball and the players' association have done the right thing in implementing a testing policy, which he called a "very good first step."

"Steroids are dangerous and the public should be educated about them," Thomas said. "Throughout my career, I have never, ever, used steroids."

Red Sox pitcher Curt Schilling (search) said that in the future, players found guilty of steroid use will suffer public humiliation.

"There's no doubt in my mind that any player who's caught after this program is implemented will have his career blacklisted forever," Schilling said. "He will never lose the label as a steroid user."

President Bush, who in his State of the Union address in 2004 called for a crackdown on steroids, watched the highlights of the hearings

But White House spokesman Scott McClellan told reporters aboard Air Force One on Friday that Bush doesn't believe that federal intervention is the way to go.

"Baseball has taken important steps to respond to concerns that have been expressed about the use of steroids," McClellan said. "It's important for baseball to continue to take steps to confront the problem."

What Did Baseball Know?

Sosa and Palmeiro were named by former American League MVP Jose Canseco in his tell-all book about steroid abuse as two players who have used the drugs. It's that book, "Juiced: Wild Times, Rampant 'Roids, Smash Hits, and How Baseball Got Big," that prompted the congressional hearings.

"Never in my wildest dreams could I have imagined my athletic ability and love for America's game would lead me to this place" to talk about this particular subject, said Canseco, who sat at the same table as the other players.

Every player who testified, except Sosa, said Canseco's book was full of lies and is nothing more than an attempt to smear and sully other players' reputations.

In his book, Canseco wrote that he personally injected steroids into McGwire, who has repeatedly denied using steroids. That, said attorney Robert Saunooke, is part of the reason that Canseco sought immunity at the proceedings. He said Canseco would not answer any questions that could incriminate him.

Saying he knew his book "would create a stir in the athletic world," Canseco said: "My heart and condolences go out to those families who lost their children to steroids."

He said he would be happy to help convey the message to youth that great athletes do not need to take steroids. He told lawmakers that he could not fully answer their questions without immunity because of concerns his testimony could be used against him, but he stressed that his appearance before the committee was voluntary.

Several congressmen gushed about the sport, recalling how as children they collected baseball cards and autographs and looked up to players. With rare exceptions, members of the committee appeared deferential and unwilling to press the players, saving their harshest criticism for baseball officials.

"Why should we believe that the baseball commissioner and the baseball union will want to do something when we have a 30-year record of them not responding to this problem?" asked Rep. Henry Waxman of California, the committee's ranking Democrat.

The wood-paneled hearing room was full when the players appeared, with camera crews lining the walls and clogging the aisles. Much of the crowd cleared out when the players left, leaving empty seats for Selig's testimony.

Lawmakers questioned baseball's new testing plan, including a provision allowing for fines instead of suspensions. A first offense could cost 10 days out of a six-month season, or perhaps a $10,000 fine.

But Selig said he would suspend anyone who fails a test, adding: "There will be no exceptions."

Selig defended the steroids policy drawn up in January, saying it's "as good as any in professional sports" and adding that he agreed to shorter bans "on the theory that behavior modification should be the most important goal of our policy."

During the question-and-answer period, Waxman asked each player if steroid use in the league was public knowledge. All players except Canseco — who said "absolutely, yes," the problem was known — said they didn't have any concrete proof that anyone was using.

"I think there was suspicion — I don't think any of us knew, contrary to the claims of former players," Schilling said, adding that he felt the problem was "grossly overstated."

Palmeiro added: "Sir, I have never seen the use of steroids in the clubhouse ... I'm sure players knew about it. I really didn't pay much attention to it."

Rep. John Sweeney, R-N.Y., went down the line and asked players if they would support a zero-tolerance policy like that practiced by the International Olympic Committee — a two-year suspension for a first offense and permanent ineligibility after the second. Only Canseco and Palmeiro gave a definitive "yes."

"I wouldn't have a problem playing under any type of standards," Palmeiro said. "Like I've said before, I've never taken it, so if you want to play under the rules of the Olympics, I welcome it."

Davis: 'We're Not Grandstanding'

Committee Chairman Tom Davis said he spoke with the attorney general's office about the immunity issue for Canseco but he couldn't make it happen in time.

Davis said the committee is "not interested in embarrassing anybody, ruining careers or grandstanding," but that steroid use is a problem that can't be ignored or downplayed.

"I am a baseball fan, I always have been. I didn't become a political junkie until the Washington Senators left town," said Davis, a Northern Virginia native. "But there's a cloud over the game I love."

Davis and Waxman said more than just the game's reputation is at risk. They are concerned about the message being sent to 500,000 steroid users in high schools.

"MLB and the players' association say this is a subject that should be left to the bargaining table. They're wrong. This is a conversation that should be held in Congress and around the dinner table," Waxman said.

He said students' idol-worship of players abusing steroids creates a challenge to society at large.

"There is an absolute correlation between the culture of steroids in high school and the culture of steroids in major league clubhouses," he said.

Parents: Hold Pros Accountable

According to the most recent FOX News-Opinion Dynamics poll, about 58 percent of Americans surveyed said they do not think most professional athletes are good role models for children today, but 88 percent said they believe athletes have a responsibility to be good role models.

"The iconic status of elite athletes in American society gives them great influence" over young people, Cummings said. "There is clear evidence that steroid use among young people is increasing" at the same time professional use is said to be pervasive.

Cummings added that steroid use also can cause long-lasting and devastating damage to individuals' health.

Sen. Jim Bunning, R-Ky., a former player for the Detroit Tigers and Philadelphia Phillies and a founder of the players' union, said that the dangers of steroid use include hypertension, blood clotting, liver damage, heart attack, stroke "and many other bad things."

He also took exception to the unfair advantage players receive by pumping up on steroids.

"Maybe I am old-fashioned," said Bunning, who once pitched a rare perfect game against the Mets. "I remember players didn't get any better as they got older. We all got worse."

He recalled playing with such legendary athletes as Hank Aaron, Willie Mays and Ted Williams. "They didn't put on 40 pounds," Bunning said. "They didn't hit more home runs in their late 30s than their late 20s. What is happening in baseball now is not natural and it's not right."

Donald Hooton, director of the Taylor Hooton Foundation, which was named after his baseball-player son who committed suicide just before his senior year of high school, blasted professional ball players for juicing up and acting as if it affects no one but themselves.

"I am sick and tired of you guys telling us you don't want to be role models ... whether you like it or not, you are role models and parents across America should hold you accountable," said Hooton, who added that steroid use played a "significant role" in his son's death.

"I believe the poor example being set by professional athletes is a major catalyst, fueling the use of steroids by our kids. Our kids look up to these guys, they want to do the things the pros do to be successful."

He also called steroid users in professional sports "cowards" when it comes to facing their fans and the nation's children.

"Why don't you behave like we try to teach our kids to behave? ... Instead you hide behind the skirts of your union and with the help of management and your lawyers, you've made every effort to resist our efforts today," he said.

Denise Garibaldi, whose son Rob, a former baseball player at the University of Southern California, committed suicide after using steroids, said books like Canseco's are full of misinformation and suggest that steroid use is OK as long as you're an adult and know what you're doing.

"I'd like to know where Dr. Canseco got his research, because what we know is that without steroid use, Rob's suffering and death would have been avoided," Garibaldi said. "There's no doubt in our mind that steroids killed our son ... he surrendered his well being and integrity, he made his choice and we must now live with the consequences."

New York Yankees slugger Jason Giambi (search), who also was subpoenaed last week, was excused Tuesday from testifying because of his involvement in the ongoing federal investigation into illegal steroid distribution.

The Associated Press contributed to this report.