On the one hand, there are many cases of people who were accused of feigning madness in order to escape punishment or gain sympathy. For example, in 1593, a man named John Darrell was accused of feigning madness in order to avoid being executed for treason. Darrell claimed that he was possessed by the devil, and he behaved in a bizarre and erratic manner. However, the court eventually found him guilty and he was executed.
On the other hand, there is also evidence to suggest that madness was often a genuine medical condition. For example, in 1621, a man named Robert Burton published a book called The Anatomy of Melancholy, which described the various causes and symptoms of madness. Burton argued that madness was a serious illness that could be caused by a variety of factors, including physical illness, emotional trauma, and hereditary factors.
The debate over whether madness was feigned or genuine was a complex one, and there is no easy answer. It is likely that both feigned and genuine madness existed in the Elizabethan era.