Whitehead investigated more than 700 cases over the course of his career.
The missing uranium was investigated several times over two decades.
Between 1857 and 1900, the Senate investigated three elections over corruption.
The program investigated over 3 million government employees, of whom 300 were dismissed as security risks.
The current study extends this past research by investigating claims from the state of Oregon over a 12-year period.
They claimed to have investigated over 10,000 hauntings during their career.
During her tenure she has investigated and prosecuted over 800 federal criminal cases.
He has at various points investigated registered lobbyists over their ties to all three of the state's current leaders.
It has investigated over 140,000 aviation incidents since its establishment.