High-tech detective work has failed to solve a puzzle from the Watergate scandal that destroyed Richard Nixon's presidency.
Forensic scientists assembled by the National Archives have been examining two pages of notes from a June 1972 White House meeting, looking for clues about what was said during an 18 1/2-minute gap in a recording of the session.
They explored impressions in the paper, analyzed ink and hoped to find evidence of missing notes on the conversation between Nixon and aide H.R. Haldeman.
But the archives said Thursday the effort didn't unravel the mystery.
The meeting came after burglars tied to Nixon broke into Democratic headquarters. The question of what Nixon knew and when was key, and it caused a sensation when investigators learned the 18 1/2 minutes had been erased.