After an unsuccessful first attempt at prosecuting Roger Clemens for lying before Congress the government began its second attempt this week. Prosecutors fumbled the first time after only a few days when the judge, Reggie Walton of the U.S. District Court, declared a mistrial after the prosecution showed jurors evidence that had been declared inadmissible.

Prosecutors are facing  pressure to secure a guilty verdict after a string of unsuccessful attempts to convict athletes from performance enhancing drug investigations. Several high-profile attempts have flamed out in recent years, costing tax payers millions and leaving the government empty-handed in its efforts to curb the use of performance enhancing drugs.

For instance, last year Barry Bonds was convicted on only one of five counts that related to a San Francisco-area steroids investigation, BALCO. Bonds was found guilty of obstructing justice and was sentenced to two years of probation and six months of home confinement. Earlier this year the federal government dropped its two-year investigation of Lance Armstrong with no explanation.  “Having gone this far, after all that has happened, the government has to win the Clemens case,” Alan M. Dershowitz, a Harvard law professor, said to Juliet Macur of the NYT. “But they have to win fairly.”

Clemens, the seven-time Cy Young Award winning star, has been charged with perjury, making false statements and obstruction of Congress. He faces a maximum of 30 years in prison if convicted on all counts. The crux of the government’s case is that Clemens used performance-enhancing steroids and human growth hormone (HGH) during his illustrious career and then lied about it when he was brought before Congress in 2008.

Prosecutors will call many of the same witnesses as the first time. Brian McNamee, Clemens’ former trainer, will testify that he gave the baseball player performance-enhancing drugs. Andy Pettitte, a former teammate and friend, will say that Clemens admitted that he has used HGH. For their part Clemens’ attorneys will claim McNamee is a liar while Pettitte is confused about the conversation that took place.

Legal experts have pointed out that the prosecutors have a hard road ahead as Judge Walton not only appears to be against the case but the prosecutors themselves. Last July Walton scolded them for showing jurors the evidence saying that even a first-year law student would have been smart enough to avoid the error. He implied that the prosecution may have purposely made the mistake. Daniel C. Richman, a criminal law professor at Columbia University, said there is the worry that Judge Walton will make things difficult for the government and decrease their odds of winning.

“Juries are very open to taking signals from judges because the judge is the one person they respect as neutral,” Richman said. “If the judge doesn’t like the case, they’ll figure it out, and an experienced judge is certainly aware of that.”

Still, the prosecution has said it is confident about their chance of success. It contends it has “overwhelming evidence” against Clemens, including cotton balls and syringes with traces of steroids and Clemens’s DNA. It remains to be seen whether a jury agrees.

Read: “Clemens Retrial Set to Begin With Prosecutors on Notice,” by Juliet Macur, published at NYTimes.com.

(Lee Davis is a Chattanooga attorney who can be reached at lee@davis-hoss.com or at 266-0605.)