What is the importance of the court scene in Volpone?

The court scene in Ben Jonson's Volpone is important as a theatrical and plot device, as it shows the audience that justice is carried out and all the malefactors will be duly convicted and sentenced. The audience sees all of this worked out before their eyes, rather than merely hearing about it secondhand from other characters later. Equally important, however, is the fact that the audience gets the pleasure of knowing Volpone's real identity so that they can laugh along with him as the other characters are fooled.
Severe sentences such as banishment for Corbaccio and loss of his profession for Voltore are matched to the particular crime committed. In the end, however, Volpone and Mosca must also pay a heavy price for their misdeeds, with the greedy Volpone left penniless. While audience members who were not of noble birth might have empathized with the harsh punishment meted out to Mosca alone, perhaps that harshness was Jonson's idea of deterring the low-born from a life of crime.