Prorogatio

In the constitution of ancient Rome, prorogatio was the extension of a commander's imperium beyond the one-year term of his magistracy, usually that of consul or praetor. Prorogatio developed as a legal procedure in response to Roman expansionism and militarization; the number of annexed territories and theaters of operations outgrew the number of elected officials available to take on military and administrative duties.

Although in theory prorogation fostered continuity under an experienced commander with "expert knowledge of local conditions," thereby increasing the chances of victory, in practice politics, often motivated by the ambitions of individuals, decided whose commands were extended. Sometimes men who held no elected public office — that is, private citizens (privati) — were given imperium and prorogued, as justified by perceived military emergencies. By the Late Republic, prorogation of provincial assignments had become the norm; by enabling individuals to accumulate disproportionate military power and wealth, the practice contributed to the breakdown of constitutional checks and balances and to the civil wars that led to the collapse of the Republic.

In his study of the praetorship in the Republic, T. Corey Brennan has argued that originally prorogation was of two types, granted either by the Roman People or by the Senate: a prorogatio was put to a vote by the People (rogare) to determine whether a provincial command should be extended; propagatio was an extension by the Senate in other cases. By the mid-2nd century BCE, the Senate had usurped the People's power, and eventually all extensions of imperium were called prorogatio. After the 190s BC, when the Senate no longer submitted its decisions on extending commands to a popular vote, the term prorogatio becomes a technical misnomer, since no rogatio (legislative bill) was involved.

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