Incompetence suddenly is becoming a very compelling defense.

Just as questions are being raised about disgraced Los Angeles Clippers owner Donald Sterling's mental state in the wake of his horrific CNN interview with Anderson Cooper, the prosecutor in the Oscar Pistorius murder trial has asked that the accused undergo a 30-day psychiatric evaluation.

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ABC News reported Tuesday that prosecutor Gerrie Nel is growing frustrated over what he feels is become a revolving door of defenses as to the reason Pistorius fired through a locked bathroom door on Valentine's Day, 2013, killing his girlfriend Reeva Steenkamp.

A day earlier, Pistorius' defense team called a psychiatrist Dr. Merryll Vorster, who testified that Pistorius was suffering from a general anxiety disorder, which would cause him to fight, rather than flee, in the face of a serious threat.

The defense is in line with that of Shelly Sterling, who said her husband could be suffering from dementia and that led to his racist remarks that led to his exile from the NBA. She is trying to keep the team.

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Pistorius is seeking an acquittal.

Nel accused the defense team of changing its strategy Vorster interview Pistorius, his family and friends, and other associates, after the trial had started.

"The timing [of the evidence] is significant," Nel told Judge Thokozile Masipa, as ABC News reported. "My Lady, the consultation happened after the evidence of the accused. There must be a reason why that consultation would take place at that time."

"Can it not be seen, my lady, as a fallback?" Nel asked.

The prosecutor accused the defense of changing its strategy twice from its original position.

"His initial defense was putative self-defense," Nel asserted of Pistorius. "Then I thought his defense was adapted to automatic firing. Now psychiatrist says he suffers from a mental disorder. We don't know which of the three versions" is Pistorius' defense, he said.

Masipa said she would rule on the psychiatric evaluation on Wednesday. If allowed, the testing would further delay an already lengthy trial.

Vorster testified that Pistorius has suffered from a general anxiety disorder since his childhood, and that the anxiety has escalated with time. She said Pistorius' mental disorder, combined with his physical vulnerability, could have influenced his reaction upon hearing an intruder in his bathroom.

The psychiatrist stressed, however, that Pistorius' condition did not impair his ability to distinguish between right and wrong and act appropriately.