The Vestals are usually presented either as an exotic cruelty or as an early instance of female power, and they were structurally both, in a way that only makes sense if the two are held together.
The privileges were real and legally exceptional. A Vestal was removed from her father's patria potestas on selection, the only Roman woman freed from male legal guardianship without passing to a husband. She could own and dispose of property in her own right, make a will, and give evidence in court without taking an oath, which no other Roman could do. She was preceded by a lictor in public, a mark of magisterial rank. A condemned criminal who met her on the way to execution was reprieved. Wills and treaties of state were deposited with the Vestals for safekeeping, because their custody was considered more secure than any archive. They had reserved seating at the games and could intercede with magistrates.
The obligations matched. Six women, chosen between the ages of six and ten from suitable families, served thirty years: ten learning, ten performing the rites, ten teaching. The central duty was the fire in the temple, which was not permitted to go out and was ceremonially rekindled each March. Letting it lapse was read as a prodigy, a sign that the state's relationship with the gods had failed, and the responsible Vestal was beaten by the Pontifex Maximus.
The chastity requirement carried the state's fortune, and this is where the arrangement turns dark. A Vestal's violation was not treated as a personal offence but as incestum, a pollution endangering Rome itself, typically identified in the aftermath of a military disaster or a plague when an explanation was wanted. Because her person was sacred, her blood could not be shed. She was therefore carried in a closed litter to the Campus Sceleratus near the Colline gate, taken down into a small underground chamber furnished with a bed, a lamp, and a little bread, milk and oil, and the entrance was sealed. The technical position was that the state had not killed her.
It was rare. Something like ten cases are recorded across roughly a thousand years. They cluster tellingly: after Cannae in 216 BC, and under Domitian, whose prosecution of the chief Vestal Cornelia in AD 91 was regarded by Pliny as a political act dressed as a religious one. Historians generally read the punishments as crisis management, a way of locating the cause of a disaster in a body the state could act on.
The end came administratively rather than dramatically. Gratian withdrew the public subsidy for the cult in 382 and declined the office of Pontifex Maximus. Theodosius banned public pagan rites in 391. The fire was extinguished, the order dissolved by about 394, and the house in the Forum passed to other uses.