PRETORIA, South Africa — Oscar Pistorius was not suffering from a mental illness when he killed girlfriend Reeva Steenkamp and was able to understand the wrongfulness of what he had done, according to psychiatric reports submitted Monday at the Olympic athlete's murder trial. The conclusions by a panel of experts, read aloud by chief prosecutor Gerrie Nel, appeared to remove the possibility that the double-amputee runner could be declared not guilty because of a mental disorder, which would result in his being committed to a mental institution. The court-ordered evaluation was conducted during a one-month break in the trial, after a psychiatrist testifying for the defense, Dr. Merryll Vorster, said that Pistorius had an anxiety disorder that may have contributed to the shooting in his home in the early hours of Feb. 14, 2013.