A US attorney is a prosecutor and defense lawyer who represents the federal government in one of the 93 defined districts of the US. The position of US Attorney is given through presidential appointment. The senate then confirms all appointments. Each US Attorney generally serves for four years. However a US Attorney can receive another appointment once his or her term is completed.
As a representative of the government, a US Attorney tends to be involved in and prosecute cases which represent the breaking of federal laws. As well, the US Attorney will defend the government in civil suits pending against it. This differs from the role of a district attorney, who prosecutes those accused of breaking state laws.
Typical cases for a US Attorney could include cases involving the prosecution of those accused of treason or sedition. Additionally the US Attorney might prosecute a suspect who has broken laws across several states, as in the case of kidnapping cases that cross state lines. A US Attorney can also serve as a representative to individuals in the government involved in civil litigation.
For example, if the Secretary of State were sued, a US Attorney would likely represent him. However, if the President or Vice President needs representation or advice, they tend to turn to the US Attorney General, another appointed position and actually a member of the cabinet.
Most often, a US Attorney will have the discretion to appoint and employ assistant lawyers, who are called Assistant US Attorneys. They may be guided in their decision as to who to appoint and purposefully groom certain lawyers with similar political ideals to take over when their term ends. However, politics is usually second place to extreme competency. Naturally any US Attorney is most interested in successful prosecution and defense.
The US Attorney may also make decisions about which cases are most likely to be successfully prosecuted. He or she may also be referred to as the Chief Federal Prosecutor for a district. The position of US Attorney has been held in some form since 1789, with obviously expanding job opportunities as the US expanded its border and population.