Quotation marks would only have to be used on thoughts if the<br />thoughts were someone else's. If the thoughts came from a book, computer source, or some other source, then quotation marks should be used. However, the writer of the essay does not have to quote his or her <i>own</i> thoughts.
As of 2011, there are at least 25,000 sworn (and armed) law enforcement officers working for federal agencies not traditionally associated with law enforcement, and 3,800 of them were specifically criminal investigators.
As of 2004, about 3 in 4 federal law enforcement officers working outside the Armed Forces were employed within the Department of Homeland Security or the Department of Justice. Federal officers' duties included criminal investigation (38%), police response and patrol (21%), corrections and detention (16%), inspections (16%), court operations (5%), and security and protection (4%).