In 342 BC, two significant laws were passed. One of these two laws made it illegal to hold more than one office at any given point in time, and the other law required an interval of ten years to pass before any magistrate could seek re-election to any office. As a result of these two laws, the military situation quickly became unmanageable. During this time period, Rome was expanding within Italy and beginning to take steps beyond Italy, and thus it became necessary for military commanders to hold office for several years at a time. This problem was resolved with the creation of the pro-magisterial offices, so that when an individual's term in office ended, his command might be prorogued ("prorogatio imperii"). In effect, when a magistrate's term ended, his "imperium" was extended, and he usually held the title of either Proconsul or Propraetor. This constitutional device was not in harmony with the underlying genius of the Roman constitution, and its frequent usage eventually paved the way for the empire. In addition, during these years, the Plebeian Tribunes and the senators grew increasingly close. The senate realized the need to use Plebeian officials to accomplish desired goals, and so to win over the Tribunes, the senators gave the Tribunes a great deal of power, and unsurprisingly, the Tribunes began to feel obligated to the senate. As the Tribunes and the senators grew closer, Plebeian senators were often able to secure the Tribunate for members of their own families. In time, the Tribunate became a stepping stone to higher office.