When Olympic sprinter Oscar Pistorius took the stand at his own murder trial on Monday, he began with an emotional apology to the family of his deceased girlfriend Reeva Steenkamp: ”I would like to take this opportunity to apologize to Mr. and Mrs. Steenkamp, to Reeva’s family," he said, adding, ”To those of you who knew her who are in court today.” He continued, saying that he was "trying to protect" her during that fateful night when he shot her on Valentine's Day of last year and that since her death he had "terrible nightmares" and often hallucinated that he could smell Steenkamp's blood. 

Pistorius, a 27-year-old South African who gained fame as the first double amputee to participate in the Olympics, faces a murder trial for Steenkamp's February 2013 death. Nobody disputes whether Pistorius killed Steenkamp: he fired his gun at Steenkamp through the bathroom door of the home they shared that night. But prosecutors and Pistorius have two very different explanations for why. Prosecutors are contending that Pistorius intentionally murdered Steenkamp after a loud, violent argument.

Pistorius's version paints the death as a mistake — he thought he heard an intruder in his home. Without his prosthetic legs on, he defended himself in the most effective way he could, by firing his gun at what he thought was an intruder. "I was simply trying to protect Reeva," Pistorius said from the stand, adding, "I can promise you when she went to bed that night she felt loved. I’ve tried to put my feelings in words to you several times, but no words ever sufficed.” Here's more from the New York Times: 

 Mr. Pistorius gave a harrowing account of his state of mind since the shooting. He has been taking antidepressants and sleeping pills, he said, and has suffered from such bad nightmares — waking up terrified, with the smell of “all that blood” fresh in his memory each time — that, he said, he is afraid to go to sleep at all. One night it was so bad that he found himself sitting in a closet in his house. He telephoned his sister for help.

Pistorius has pleaded not guilty to the murder charge. Monday marks the first time he has spoken in his own defense since the trial began last month, though his testimony about the actual shooting will not come until tomorrow. If convicted, he faces a minimum of 25 years behind bars.