Michael Kopper, once the top lieutenant to former Enron chief financial officer Andrew Fastow was sentenced Friday to three years and one month in prison for his role in crimes that led to the company's collapse.

Another former Enron executive was awaiting his sentence.

Prosecutors had asked that Kopper and Mark Koenig, the company's former investor relations director, be given reduced sentences for their cooperation.

The men were being sentenced separately by U.S. District Judge Ewing Werlein Jr.

Kopper, 41, was the first former Enron executive to plead guilty to charges related to one of the largest corporate scandals in history.

He led federal prosecutors to Fastow, who in turn led them to Enron founder Kenneth Lay and former chief executive Jeffrey Skilling.

Fastow just began serving six years in a federal prison in Louisiana. Lay and Skilling were convicted in May of conspiracy and fraud. Lay's convictions were wiped out with his July death from heart disease. Skilling was sentenced last month to more than 24 years in prison and will begin serving his sentence next month at a low-security prison in Minnesota.

Kopper pleaded guilty in 2002 to money laundering and conspiracy to commit wire fraud and could be sentenced to 15 years in prison. He also surrendered nearly $12 million in ill-gotten gains.

"Put simply, Mr. Kopper's assistance was invaluable to the government's efforts to get to the bottom of what happened at Enron and to charge culpable individuals," prosecutor Kathryn Ruemmler wrote in a court filing this week.

Prosecutors said that from May 1997 through September 2001, Kopper took advantage of off-balance-sheet partnerships and accounting methods to funnel millions of dollars to himself, Fastow and others at the expense of the company and its shareholders.

In the year prior to Enron's collapse, Kopper, who had a taste for Armani suits, earned $3.63 million in salary, bonuses, restricted stock and other payments. He had a $1.4 million marble and stucco four-bedroom house and along with his domestic partner, owned four BMWs.

Koenig, 51, who helped present the company's false financial reports to investors, pleaded guilty in August 2004 to one count of aiding and abetting securities fraud, which carries up to 10 years in prison.

Ruemmler said Koenig warrants a substantial reduction in his sentence because his assistance resulted in the guilty pleas of other Enron executives and contributed to the successful prosecution of Lay and Skilling.

"Perhaps more significantly, however, Mr. Koenig has embraced the spirit of full cooperation through his genuine remorse, his commitment to the truth and his efforts to right his wrongs through his actions," Ruemmler wrote in another court filing this week.

Koenig was the government's first witness in Lay and Skilling's trial earlier this year.

During his seven days on the stand, Koenig told jurors that Enron, bent on matching or beating Wall Street expectations, fudged its earnings figures with the knowledge of Skilling and Lay.

In his role, Koenig worked with both men, serving as the company's main link to investors and analysts. He coordinated analyst presentations and oversaw the company's earnings announcements.

Earlier this week, Richard Causey, the company's former chief accounting officer, was sentenced to 5 1/2 years for his role in the company's collapse.

Enron, once the nation's seventh-largest company, crumbled into bankruptcy proceedings in December 2001 after years of accounting tricks could no longer hide billions in debt or make failing ventures appear profitable. The collapse wiped out thousands of jobs, more than $60 billion in market value and more than $2 billion in pension plans.