Why did Oscar Pistorius kill Reeva Steenkamp?

Oscar Pistorius admitted that he had murdered his girlfriend Reeva Steenkamp. But the athlete stated that he had shot her because he had mistaken her for an intruder.
Police officers try to determine why the Olympic athlete really killed Reeva Steenkamp. They discovered anabolic steroids at his home.
Since anabolic steroids have been discovered in Oscar’s bedroom, it would be probably argued that anabolic steroids caused uncontrolled behavior in the athlete. Anabolic steroids would be blamed for the murder.
In fact, you should recognize that it is quite hardly to claim that anabolic steroids are responsible for aggression and violent behavior. Researches linked with this issue are quite limited. According to results of some researches, steroid users are predisposed to aggression, paranoia, jealousy, etc. It is stated that those who apply anabolic steroids are more likely to commit crimes than those who have nothing to do with these products. But it is important to take in consideration that anabolic steroids may just contribute to aggression. Only these drugs alone can’t cause aggression. They turn out to be only contributive factors. Other factors should be also present for appearing of aggression. Circumstances play essential role in such cases. So, it is even impossible to define whether anabolic steroids cause aggression or several circumstances. Violent cases should be viewed as a complex of steroid use and circumstances.
It is also stated by scientists that increased levels of testosterone are associated with aggression in several individuals. Thus, it is necessary to notice here that while some individuals with elevated testosterone levels experience aggression, others with elevated testosterone levels are not predisposed to uncontrolled violence. This condition differs from one person to another.
You can note that the connection between administration of steroids and violence is a complicated issue. Scientists have not studied this condition well enough to implicate it. Thus, if defense lawyers of the Olympic athlete want to argue that anabolic steroids have made their client to murder his girlfriend, they should understand that they are going to utilize controversial statements.