NEW YORK (CNNMoney.com) - The light at the end of the tunnel continues to be elusive for Enron founder Kenneth Lay who could find himself spending life in prison even if he is acquitted by a jury for allegations that he helped bring about Enron's collapse.

With closing arguments in the securities fraud case against Lay and former chief executive Jeffrey Skilling set to begin Monday, jurors are expected to begin deliberations by midweek. And then the focus will shift from corporate fraud to Lay's own personal finances as he returns without Skilling to the courtroom in order to answer four separate criminal charges alleging that he convinced banks to loan him $75 million under false pretenses.

Eron founder Ken Lay.

But, this time Lay won't have the luxury of appealing to 12 jurors. Instead he will stand before Judge Sim Lake, the same judge that has presided over his first trial, and attempt to convince Lake that he is innocent of any fraud.

It's an odd sort of double jeopardy for Lay but a brilliant strategy for the prosecution, legal experts said.

"The prosecution is hedging their bets," said John Bielema, securities enforcement defense partner at Atlanta-based law firm Powell Goldstein LLP. "If for whatever reasons the jury acquits Lay on the securities fraud charges, they've still got bank fraud. They're coming out with multiple charges and hoping that one sticks."

The issue revolves around an obscure banking law from the Depression-era, called Regulation U, which limits the amount of credit a bank can extend to customers for buying on margin. The purpose of the law is to prevent banks from taking on too much risk.

Government prosecutors allege that Lay signed documents at Bank of America (Research), Chase Bank Of Texas and Compass Bank (Research) in which he agreed that he wouldn't use the $75 million in credit lines to buy or maintain stock on margin but then proceeded to do exactly that.

If he's convicted, Lay faces up to 30 years in jail for each count.

The defense team for Lay is remaining mum ahead of the May 18 trial date but on Lay's official website, the Houston icon denounced the charges saying "they are based on arcane laws" and added that "my legal team can find no record during this law's 70 year existence of these provisions ever being used against a bank customer [like me] until now."

And the defense contends that Lay paid back the $75 million loans to the banks, making this a victimless crime.

That may be true, but legal experts said that Lay faces a real threat, especially as the case falls before Judge Lake, a no-nonsense judge known to follow the letter of the law.

It's an unusual situation but one that Lay's defense team inadvertently created. Originally the four bank fraud charges were included in the overall indictment against Lay, Skilling and former accounting chief Richard Causey -- who pleaded guilty in late December 2005, just weeks before the trial was set to begin.

Lay's defense team insisted on a speedy trial and offered to waive Lay's right to a jury trial in order to expedite the case. But the ploy backfired when Judge Lake separated the four charges - which were not related to Enron but rather Lay's own personal finances - and Lay waived his right to a jury trial in the bank fraud case.

With that ruling, Lay lost the ability to charm and convince 12 jurors unfamiliar with Regulation U that it didn't apply to his case. Instead, his fate fell into the hands of the judge. Legal experts agree that judges tend to be more systematic and particular about holding up the law.

And Lay has the added misfortune of facing Judge Lake only a couple of weeks after he took the stand in his own defense related to six charges of conspiracy and fraud at Enron.

"To have the same judge presiding over a second trial while the jury is still deliberating [in the first trial] is nothing short of remarkable," said Sheldon Zenner, head of the white collar litigation group at Chicago-based law firm Katten Muchin Rosenman."You have to presume that the judge, try as he might to review the second case independently, can't help but be influenced by what he's seen in trial one."

To that end, Lay's performance on the stand was nothing short of dismal. The former leader, known for his affable demeanor, appeared testy and argumentative as he attempted to seize control of the direction of both the prosecution's line of questioning as well as that of his own defense attorney, George "Mac" Secrest.

And Judge Lake frequently appeared frustrated with Lay's defense team during his testimony, even admonishing Secrest at one point by saying harshly that "We've got a lot of wasted time so far in this direct examination."

Legal experts said while it's unlikely that Lay will take the stand to defend himself during his bank fraud trial, he will be at a disadvantage because Judge Lake has already been able to make judgments about his credibility based on the first trial.

"[Judge Lake] is bound to view the facts in the second case separate from anything he's seen or heard in the first case and he will strive mightily to do that," Zenner said. "On the other hand, he is human and human beings make judgments based on their experience."

Unlike the securities fraud trial for Lay and Skilling which will enter its sixteenth week Monday, the bank fraud trial is expected to last only a few days. But the judge will not render a verdict until the jury returns with its verdict on the first trial.

And therein lies another danger for Lay, said Bielema of Powell & Goldstein.

Bielema said even if Lay wins the battle with the jury -- a possibility that legal experts believe became increasingly remote after his performance on the stand -- he could lose the war with the judge.

"Whether you're in jail for securities fraud or bank fraud isn't going to make a whole lot of difference if you're still looking out at the world from behind bars," he said.

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