Gay rights campaigners have complained to police about some of reggae's biggest stars over lyrics they say incite violence against homosexuals.
Beenie Man is one of the world's biggest reggae stars
Beenie Man, Elephant Man and Bounty Killer - all nominated for Mobo Awards - are "reggae bigots", according to Peter Tatchell of the group Outrage!
The Mobos should withdraw their nominations, he said - but organisers have refused and denied any homophobia.
A Metropolitan Police spokeswoman said they were studying the complaint.
She told BBC News Online: "The Met has received a complaint today alleging songs of a number of reggae artists nominated for a 2003 Mobo Award incite homophobic assault and murder due to the lyrics.
"Officers from the Met's diversity directorate are currently studying the details of this allegation."
Peter Tatchell demonstrated at the Mobos in 2002
OutRage! says the singers, who are all Jamaican, have lyrics that tell listeners to do things like "murder dem fast just like a Federal Express".
The artists are all nominated in the best reggae category of the Mobos.
Mr Tatchell accused the awards of "rewarding bigotry", but organisers said the artists were not nominated for songs with homophobic lyrics, and banning them would be censorship.
Mr Tatchell said: "It is the moral equivalent of the Brit Awards nominating a racist entertainer who incites the killing of black people.
"The Mobo organisers should withdraw these nominations immediately, and apologise to the gay community for their collusion with these entertainers' homophobic abuse and threats."
The record companies representing the artists were unavailable for comment, but Beenie Man has reportedly apologised for some of his past comments.
A Mobo spokeswoman said the artists would not travel to London for the award ceremony on 25 September.
A statement from the Mobos said they denied "all claims of homophobia" and they were "totally appalled" at any discrimination.
"Any attempt to tamper with and make judgements on the various artists that are nominated by the UK recording industry would be tantamount to censorship," it said.
"Musicians and artists have always reflected the feelings of the wider community they come from, regardless of whether or not everyone wants to hear what is being said on a street level."
If artists sang about situations they saw around them, it did not necessarily mean they held those views, the statement said.
Beenie Man is the best-known of the trio, with four top 20 singles in the UK.
Meanwhile, rap superstar 50 Cent - who is not among those accused - has been confirmed as one of the performers at the awards ceremony, to take place at the Royal Albert Hall.
Event organiser Kanya King told BBC 6 Music the rapper had enjoyed a "phenomenal year", in an interview with the station's Tom Robinson to be broadcast next week.