It's the dog days of August. The pennant races are on. The Colorado Rockies and San Francisco Giants are jockeying for a wild card spot. The Boston Red Sox are imploding. And the Tampa Bay Rays are surging.

But those aren’t the biggest stories in baseball.

The top news is that Red Sox designated hitter David Ortiz is defending himself against charges that he used steroids.

The pennant races may simmer. But the discussion of performance enhancing drugs in the national pastime remains white hot.

And it’s all because of an historic Congressional hearing more than four years ago.

Crowds of fans clutching balls and wearing jerseys lined the halls of the Rayburn House Office Building as the immortals entered the House Government Reform and Oversight Committee hearing room on March 17, 2005.

Jose Canseco, Rafael Palmeiro, Sammy Sosa and Mark McGwire strode in like Colossuses. But after a few hours of Congressional browbeating, the players departed, a shadow of the looming figures they once cut on the diamond.

When he entered the hearing room, the once bloated, Mark McGwire, who boasted 19-inch biceps, resembled a deflated balloon. And the man who crushed a then-record 70 home runs in 1998 didn’t do himself any favors as he repeatedly deployed a Fifth Amendment shield against potential self-incrimination.

“I’m not here to talk about the past. I’m here to talk about the positive,” was McGwire’s refrain that day.

McGwire drew the ire of Rep. Mark Souder (R-IN).

“This is an oversight committee. If the Enron people come in here and say well we don’t want to talk about the past, you think Congress is going to let them get away with that?” scolded Souder.

Souder then pointed out that Congress specifically exempts Major League Baseball from anti-trust laws, which helps boost already staggering player salaries.

“How are we supposed to figure out what our obligation is to the taxpayer when you’re a protected monopoly and you say you’re not going to talk about the past?” Souder queried.

At the same winter 2005 hearing, former Rep. Chris Shays (R-CT) took aim at Baseball Commissioner Bud Selig. Shays grew exasperated as Selig tried to explain to lawmakers baseball’s steroid policy.

“The more I learn about what you do, the more questions I have about the hell it is you do, do,” Shays blistered.

The 2005 hearing set in motion events that still reverberate today. Like all players sitting at the witness table, former Baltimore Orioles first baseman Rafael Palmeiro was defiant that he wasn’t on the juice.

“I have never used steroids, period,” Palmeiro proclaimed, pointing his finger at lawmakers assembled on the dais.

In August of that year, baseball suspended Palmeiro for ten days for violating the game’s anti-steroid rules.

That prompted the committee to investigate whether Palmeiro lied under oath. In the end, Congress determined there wasn’t enough evidence to charge Palmeiro with perjury. But the man who ordered the report, former Rep. Tom Davis (R-VA) noted that the verdict  wasn’t “a finding of innocence.”

Palmeiro later suggested a potential explanation for failing his drug test. He said that former Orioles teammate Miguel Tejada provided him with a shot of vitamin B-12. But it’s unclear what the vial contained.

As part of its perjury probe involving Palmeiro, Congress deposed Tejada, the 2002 American League Most Valuable Player and now a shortstop with the Houston Astros.

House investigators didn’t place Tejada under oath during the deposition. But court documents reveal that Congress advised Tejada “of the importance of providing truthful answers.”

Tejada told Congress that he wasn’t aware of an ex-teammate using drugs to help his performance on the field. But later, the House alleged that Tejada “unlawfully withheld pertinent information from the committee.”

Davis told the Associated Press that he felt Tejada didn’t tell the truth.

The House then referred Tejada to the Justice Department for a criminal probe. In February of this year, Tejada pleaded guilty to lying to Congress. He received a year of probation.

The 2005 hearing set two other events into motion. First, baseball bolstered its anti-doping policies. Stricter penalties led to this summer’s 50-game suspension of Los Angeles Dodgers slugger Manny Ramirez. Secondly, it prompted baseball to commission the “Mitchell Report,” an inquiry into the use of performance-enhancing substances in the game by former Senate Majority Leader George Mitchell (D-ME). In the end, Mitchell named 89 current or former players who allegedly used illegal substances.

Seven-time Cy Young Award winner Roger Clemens was one of the most-prominent names on Mitchell’s list. Clemens later said that he “did not take steroids, human growth hormone or any other banned substances at any time in my baseball career or, in fact, my entire life.”

After facing a fusillade of accusations from former trainer Brian McNamee, Clemens pleaded with the House Oversight and Government Reform Committee for an opportunity to rebut those claims in public.

At a February, 2008 hearing, Rep. Elijah Cummings (D-MD) told Clemens “it’s hard to believe you sir.”

The committee, by that point under the leadership of Rep. Henry Waxman (D-CA), announced that “Clemens made statements that we know are untrue.”

When Clemens attempted to interrupt Waxman, the chairman cut him off and slammed down his gavel hard.

“This is not your time to argue with me,” the 5’6” Waxman chastened the 6’4” Clemens.  

Congress then referred Clemens to the Justice Department for potentially committing perjury. That investigation remains open.

So more than four years after the March 17, 2005 hearing, the specter of performance-enhancing drugs still clouds the game. Sure, fans are pulling for their teams during the stretch drive. But there’s murmuring about David Ortiz. Questions about Alex Rodriguez of the New York Yankees. All-time home run king Barry Bonds remains under indictment for perjury and obstruction of justice and is awaiting trial. No one really knows how deep drug use could run in the game.

That’s why Major League Baseball remains haunted by an eerie line uttered by former Congressman Tom Davis at the March, 2005 hearing. As chair of the committee at the time, Davis appropriated a line from the touchstone of baseball’s literary canon, “Casey at the Bat.”

“Somewhere men are shouting. And somewhere children shout,” said Davis. “But there’s no joy in Mudville until the truth comes out.”

And four years later, the game has stretched well into extra-innings.

- Chad Pergram covers Congress for FOX News. He’s won an Edward R. Murrow Award and the Joan Barone Award for his reporting on Capitol Hill.