Trayvon Martin: Barack Obama says America should do some 'soul searching' In his remarks, President Obama appeared to suggest that Stand Your Ground should now be reviewed, as he called for a thorough investigation into every aspect of the case. "I think every parent in America should be able to understand why it is absolutely imperative to investigate every aspect of this and that everybody pulls together - federal, state and local - to figure out exactly how this tragedy happened," he said. I think all of us have to do some soul searching to figure out how does something like this happen. And that means we examine the laws, the context for what happened, as well as the specifics of the incident. Until now, the White House had been careful not to become involved with an ongoing investigation, despite the rising national outrage and accusations of racism. But President Obama made clear his sense of empathy with Trayvon's parents, Tracy Martin and Sybrina Fulton. "My main message is to the parents of Trayvon Martin: If I had a son he'd look like Trayvon," he said. And I think they are right to expect that all of us as Americans are going to take this with the seriousness it deserves and that we're going to get to the bottom of exactly what happened. Trayvon was killed nearly four weeks ago, as he returned from a grocery store where he had bought a packet of sweets for his younger brother. Mr Zimmerman had a history of calling police to his mainly-white gated community, and when he dialled the emergency services he claimed that he had seen a suspicious suspect who was "probably on drugs." Police told him not to follow the suspect, but Mr Zimmerman did not obey, and a girlfriend who was on the phone to Trayvon at the time claims she heard him being shoved to the ground. Neighbours heard screams for help before a shot rang out. The head of Sanford police stood aside "temporarily" earlier this week amid complaints that the investigation was flawed, as Trayvon's phone records, which would have led to his girlfriend, were not looked into. Mr Zimmerman's whereabouts is unknown - his father has denied that he is racist, and says that he himself is Hispanic, and so also of an ethnic minority background.