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.
The law enforcement agency headed by a sheriff is commonly referred to as a sheriff's office or sheriff's department. According to the National Sheriffs' Association, an American sheriff's advocacy group, there were 3,085 sheriff's offices and departments as of the end of 2008.