Barack Obama says all Americans have some "soul-searching" to do after the killing of black teenager Trayvon Martin.
The US President said a full investigation is needed into the shooting of the unarmed Florida teen by a neighbourhood watch captain.
The 17-year-old was shot dead last month by George Zimmerman, who claims he acted in self-defence - an argument protected under a controversial state law.
Asked about the incident, which has sparked outrage across the US , Mr Obama said it was a "tragedy" that had made him think of his own two daughters.
"My main message is to the parents of Trayvon Martin. You know, if I had a son, he'd look like Trayvon.
"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 are going to get to the bottom of exactly what happened."
On February 26, Trayvon had been to a convenience store in the city of Sanford, where he was visiting family.
He was walking back carrying a packet of Skittles and a can of iced tea, with the hood of his jacket pulled over his head because it was raining.
He was approached by 28-year-old Mr Zimmerman, who told an emergency call operator he thought the teen looked suspicious.
Mr Zimmerman then shot and killed Trayvon following a chase and fight.
The US justice department and FBI have opened a civil rights investigation, and a grand jury is considering whether to charge Mr Zimmerman.
Florida has a law known as "stand your ground", which allows the use of deadly force if someone believes they are in danger of imminent death or great bodily harm.
Police did not arrest Mr Zimmerman at the time of the shooting and have refused to arrest him since.
Campaigners are now calling for the law to be overturned.
Trayvon's parents have started an online petition demanding Mr Zimmerman's arrest. So far, it has more than 1.4 million signatures.
Mr Obama added: "I think all of us have to do soul-searching to figure out how does something like this happen and that means we examine the laws and the context for what happened."