MIAMI - Seven fingerprints on a purported al-Qaeda training-camp application came back as matches to alleged terrorist operative Jose Padilla, a government expert testified yesterday.

But Secret Service fingerprint specialist John Morgan also acknowledged under defense questioning that there was no way to be certain when the fingerprints were placed on the "mujahedeen data form" recovered by the CIA in Afghanistan.

Defense lawyers theorize that Padilla, 36, a U.S. citizen and former Chicago gang member, may have touched the form during his confinement at a Navy brig in Charleston, S.C. He was held for 31/2 years as an enemy combatant before his indictment in late 2005 in the Miami terrorism-support case.

Although the form was one of dozens found in a binder in late 2001, it was not analyzed for Padilla's fingerprints until August 2006, Morgan said. The fingerprints appear only on the front of the first page and back of the last page, possibly indicating that the form had been simply handed to Padilla at some point, defense lawyers say.

"Is it also possible that these prints were made by someone who was writing on the document?" prosecutor John Shipley asked.

"Yes, that is possible," Morgan answered, adding that fingerprints were not always left behind when someone touched a paper. "It can go both ways."

Prosecutors have opened the trial of Padilla and two codefendants by focusing on the form, which they contend Padilla completed in July 2000 to attend the al-Farooq training camp. The form is critical because it potentially links the three defendants to al-Qaeda as one of the Islamic extremist groups they are accused of conspiring to support.

Earlier this week, a CIA officer testified that the form was brought in December 2001 to an agency installation in Kandahar, Afghanistan, by a man who said he had found thousands of documents from what he believed was an al-Qaeda safe house after its occupants fled.

The partially completed five-page form includes Padilla's birth date, Oct. 18, 1970, and lists the nickname Abu Abdallah Al Muhajir, which prosecutors say was an alias for Padilla. The applicant wrote that he was a native speaker of English and Spanish, with carpentry skills, who studied Arabic and the Koran, made a hajj pilgrimage to Mecca, and went to Yemen "as a way to go through for Jihad."