The request comes in response to testimony offered by a psychiatrist Monday that Pistorius suffers from an anxiety disorder brought on by the childhood trauma of a double amputation and unstable parents.
Although Pistorius' defense team has asserted that the amputation amounted to a "traumatic assault," they have not submitted an insanity or capacity defense for Pistorius' actions on February 14, 2013.
Pistorius has admitted he shot girlfriend Reeva Steenkamp but claims that he mistook her for a burglar in the bathroom of his residence.
Psychiatrist Dr. Meryl Vorster testified Monday that Pistorius and his siblings were raised by their mother "to see their external environment as threatening," an upbringing that "added to the anxiety."
The prosecutor's request for an independent mental health exam could delay the trial for more than a month.