If a recent controversial rap video on racism was allowed to remain online - as some have called for - then other videos with racially offensive speech will have to be permitted too, Law and Home Affairs Minister K. Shanmugam said yesterday.

This would come at the expense of minorities here and worsen racism in Singapore, he said at a discussion on race organised by the National University of Singapore's Department of Communications and New Media (CNM).

Explaining why the Government had ordered the video by YouTube artist Preeti Nair and her brother to be taken down, the minister said: "If we allow the line to be crossed... then it is free for all, the Chinese can be equally offensive, and the minorities will be the losers in such a conversation."

But noting that it was important to have frank discussions about race and for people to express themselves, Mr Shanmugam said of the video: "The only thing that is being objected to is the tone."

"When you use offensive language, others will use offensive language, and it takes a completely different dimension," he added, citing as example countries like Germany, where the political culture is becoming more brutish, and the far right more violent.

Mr Shanmugam was speaking to about 100 university students, staff and members of the public at the biannual CNM Leaders Summit, where participants get to engage key political and industry leaders on specific issues.

Racism was the main topic yesterday, in the light of an ad to promote e-payments which featured a Chinese actor in "brownface", playing a man with visibly darker skin and a woman in a tudung.

In response to the ad, Ms Nair and her brother, rapper Subhas Nair, created a parody rap video containing four-letter words and vulgar gestures to call out the racism by Chinese Singaporeans.

The siblings were given a conditional warning by police, while the Infocomm Media Development Authority handed a stern reminder to those involved in the ad on the importance of paying attention to racial and religious sensitivities.

Mr Shanmugam said the laws must apply equally to all, and if the rap video were permitted, this would mean the Chinese can do likewise and make similar racially offensive videos about Malays and Indians.

"In any society, 95 per cent of the people would not go and do these things and attack another race. But if you allow the 5 per cent to do it, over time, that will become 10, 15 per cent," he said. "Once it becomes normalised, it is perfectly normal to talk about each other along these lines," he said.

"Then to what extent do you think we will be able to have that kind of interactions we have today, where by and large the races co-exist and conduct relationships on a certain basis of respect and trust?" he asked the audience.

He cited a poll by Government feedback unit Reach of more than 1,150 people in which it was found that while awareness of the recent controversy was high, only about one in 10 actually watched the video. The majority, or 76 per cent, supported the Government stance of removing such videos from the Internet, the survey showed.

Asked whether the decision to censure the video could have been left to society, he said the clip crossed the line of criminality.

"If society feels such a video in the future should not be considered to be in breach, then the law will have to change.

"And you are the people who are going to determine what the laws ought to be because the laws reflect the social values and mores of society," he said.

Mr Shanmugam said he feels there should be a conversation, preferably from the ground up, on race and religion.

"It is a topic that is trending now, and people are aware of it. We should discuss it - how do the minorities feel, how do the majorities feel. Have this openness in the conversation," he added.

Q&A with Shanmugam on racism and censorship

Q Have we become more race conscious? When we had (television sitcom) Phua Chu Kang in the 1990s, there was no reaction from the community. Half Indian, half Chinese actor portraying a Chinese contractor. Now, with the "brownface" ad, there is such a strong reaction.

A I think the lesson for us is that social values and mores have changed. Today, more people think a Chinese playing... (someone) of another race, in some way, demeans the other race.

I think we were more race conscious 10 to 15 years ago, and more racist. We are less race conscious and less racist (now), and therefore I think we are more quick to accept that others might take offence.

Q During the Nets e-pay opening ceremony, there were one or two ministers present there and the ad was also shown, but there was no response until someone else started questioning it.

A I don't know how much attention they paid to these ads. I don't know how long these ads were shown... Having been to many of these events, there are things that you pay attention to, there are things you may overlook. If you are asked to go on stage, you take a photo, you are not necessarily observing every single thing that is on the stage or the platform.... So, I don't know what it is that they saw. I am not avoiding your question. But these are facts. You have got to see what it is they saw before you jump to conclusions.

Q With regard to Watain, the Swedish black metal band, how does the Singapore Government decide when it needs to act? Is it a pure numbers game - 100 music fans versus 110 people who complained?

A We take into account, first, objectively, the words; doesn't matter how many people.

Second, the impact on the community, and you balance these together with other situations you have dealt with, and then you come to a judgment call. I cannot give you a clean black-and-white answer.

If we applied the same line when we banned The Satanic Verses (by Salman Rushdie) to other literature, a large part of Western literature would have been banned, which we are nowhere intending to do.

My speech (in Parliament in April) gives more.