Secret Service Told To Talk

For the first time in history, officers of the Secret Service have testified before a grand jury in a criminal investigation of the president, reports CBS News Senior White House Correspondent Scott Pelley.

Watch CBS News Senior White House Correspondent Scott Pelley's Full Report

The chief justice of the United States, William Rehnquist, refused a late Clinton administration appeal to stop the testimony.

Eleven secret service men were summoned to the grand jury including Larry Cockell, the head of the president's personal security detail. The first to testify was Robert Ferguson, a recently retired agent who also served on Mr. Clinton's detail. He was followed by three uniformed officers who guard the corridors by the oval office.

What are prosecutors asking the Secret Service?

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From sealed court documents, CBS News has obtained a list of Starr's questions that Secret Service officers refused to answer in earlier interviews.

They include:

Was Monica Lewinsky ever in the Oval Office?
Were Lewinsky and the president ever alone together?
Did any officer "witness the president in a romantic situation or engaged in a sexual act?"

Finally, the officers have been asked about White House steward Bayani Nelvis, who works around the Oval Office. Prosecutors wanted to know if Nelvis told the officers of a relationship between Lewinsky and the president.

The questions are aimed at discovering whether Mr. Clinton and Lewinsky lied under oath about an affair and encouraged others to commit perjury

Watch CBS News Legal Correspondent Kristin Jeanette-Meyers' Discussion Of The Legal Issues Raised By Secret Service Testimony

Before the grand jury, the officers would be compelled to answer.

Sources tell CBS News that all of the uniformed officers knew Monica Lewinsky and saw her often. Cockell, the head of the president's detail, did not testify. He may be the least important witness - sources say Cockell will tell the grand jury he didn't know Lewinsky or witness anything improper.

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