He used the word "a-hole" to describe someone on radio because he was irritated by the "constant complaints" of a visually-impaired person on Facebook.
Then, his fellow DJ went all the way and called him an "a** hole" for using that word. The use of such strong language surprised some listeners of Class 95FM.
The Media Development Authority (MDA) said it had been notified and is "reviewing the case".
The incident happened during the Morning Express show on Thursday, a radio programme hosted by DJs Joe Augustin and Glenn Ong, both 44.
During a 40-minute segment, the pair, known to ham it up for radio by taking opposing views, engaged in what appeared to be a heated discussion over the actions of Ms Cassandra Chiu, who is visually impaired.
Ms Chiu, who is one of the Singapore Woman Award 2012 winners, had posted on Facebook that she had been denied service at a McDonald's outlet in Jurong Park on Monday after she had walked in with her guide dog Esme.
Ms Chiu, who began to lose her sight at age eight due to a degenerative eye condition called Stargardt disease, has a Facebook page called Esme The Guide Dog in which she writes as Esme.
After her encounter at McDonald's on Monday, she had posted on Esme's account: "They just refused to serve us because it's free muffin day and blind people are not entitled."
Her generalisation and presumption of what took place had upset Augustin.
Ms Chiu is known on Facebook for being rejected at local establishments here such as clothing store Forever 21 in 2012 and ice-cream shop Haagen-Dazs last year because Esme was perceived as her pet and was not allowed the shops.
While discussing her latest post, Augustin then called Ms Chiu an "a-hole" for her constant complaints and "inflammatory remarks" that the visually impaired were being discriminated against and denied McMuffins at McDonald's. Ong then appeared to be offended, and called him an "a**hole" for calling Ms Chiu that.
Listeners were then called in to give their opinions on whether they agreed with either DJs over Ms Chiu's Facebook post.
Ong told The New Paper: "I was shocked that Joe would say this about someone as well-regarded as Cassandra. I think she was justified and she had every right to kick up a fuss.
"Cassandra and Esme's latest encounter was a brush with stupidity, as far as I'm concerned.
"I mean the law allows seeing eye dogs everywhere, yet she has to work so hard to make establishments realise this. I think this latest episode was the straw that broke the doggy's back."
Augustin, on the other hand, told TNP: "What happened (Ms Chiu being refused service at McDonald's) should not have happened.
"But what I was vocal about was what I thought of Cassandra's constant complaining.
"For me, it was the action and manner in which the subject was broached on her dog's Facebook page that was too much."
Both DJs didn't comment on the use of their choice of words, but Ong said he embraced their straight-talking DJ-ing style.
"Being real on radio (and calling it like it is) rocks," added Augustin.
While it is unclear if the on-air banter was staged, listeners were divided over whether the DJs should use such strong language.
While some listeners lauded Augustin and Ong for their "refreshing take on a social issue", others questioned the use of such language.
'JUST BEING HONEST'
Said lawyer Dominic Thein, 42: "I like it that these guys don't censor themselves because that's what a talk show should be about. They weren't malicious or anything, just being honest. It's not like they used the F-word or anything."
Housewife Chen Fong May, 39, disagreed, and said she was concerned that her nine-year-old son would pick up words that he hears on air.
She said, laughing: "I know that my son will eventually come to know of such words like a**hole. But for now, I would like him to focus on getting his English right and proper first.
"I can't imagine what I'd do if he went around calling people a**hole at this age."
Radio DJs have, in the past, been fined for their antics on air.
In 2003, UnionWorks was fined $15,000 for featuring explicit sex discussions on WKRZ 91.3FM.
A year later, 987FM was fined $30,000 for carrying sexually suggestive segments on its show Morning Madness.
In 2007, MediaCorp Radio was fined $15,000 when DJs Justin Ang and Vernon A of 987FM's morning show got beauty pageant contestants who were in the studio with them to take off their bras without exposing themselves. Video clips of the show were also put on the Internet.
According to MDA guidelines, Clause 3.4 of the Free-to-Air Radio Programme Code states: "Obscene or offensive jokes, words, songs, dialogue should not be broadcast."
But TNP understands that MDA takes a number of factors into consideration when assessing content, including the context and presentation. To put it in layman's terms, there is no list of words that cannot be used on air because the law would have to be changed each time a new, offensive word is coined.
Hot FM91.3 DJ Shan Wee and Power 98 DJ Jamie Yeo said there are many other ways to express the same sentiment without using offensive words.
Said Wee, 31: "I don't think young minds are being corrupted when 'stronger words' are used.
"I would say that most DJs know the list of words which are too unsavoury for radio (and thus would find a different way of saying it)."
Said Yeo, 36: "I would have used jerk, idiot or said that what someone did was terrible...
"I'm not a prude, but this is about pushing the boundaries on radio.
Chiu's Facebook post on McDonald's got netizens talking
Psychotherapist Cassandra Chiu, 34, and her guide dog Esme were in the news again last week.
Her Facebook post about how she was treated on Monday at the Jurong Park McDonald's outlet became a talking point among netizens.
It was picked up by news media on the same day.
In September last year, the pair was not allowed into the Holland Village Haagen-Dazs outlet, despite presenting the manager with a photo identity card supported by the Ministry of Social and Family Development to allow guide dogs into public places. They and a group of friends eventually left.
This time round, Ms Chiu and her friend, who went to the McDonald's outlet to pick up hash browns and coffee to go, were "refused" service during the fast-food chain's islandwide free breakfast promotion that morning.
"As soon as we stepped into the outlet, there were a few people who shouted 'no pets'," Ms Chiu wrote on the Facebook page entitled Esme the Guide Dog.
She said the outlet manager came out to apologise, but said that while McDonald's is guide dog-friendly, the staff could not serve them as there was no space in the outlet due to the free Egg McMuffin giveaway.
Ms Chiu and her friend left without buying food. The incident happened two days after the arrival of the fifth guide dog, Melba, in Singapore.
Ms Chiu told The New Paper she was not blaming anyone when she posted the incident online.
"I was merely bringing awareness of the presence of guide dogs in our community and hoping to change the mindset of people; that those with handicaps do also want equal rights," she said.
On Class 95FM DJ Joe Augustin calling her an "a-hole", Ms Chiu said: "It's not ethical to encourage others to accept the view that just because I have a guide dog, I shouldn't have a voice."
Responding to questions by TNP, a spokesman for McDonald's said its policy is to be accepting of guide dogs.
"Upon learning of this, the manager in charge of the restaurant immediately apologised as he was aware of our policy on guide dogs, and offered to assist the customer with her order (and)...it was not our manager's intention to cause any offence or to refuse service," she said.
The fast-food chain invited Ms Chiu back to the restaurant to review what took place, but she declined.
McDonald's "takes this matter most seriously" and has counselled all the staff members involved, its spokesman said.
"We will look into ways to strengthen our training efforts for our crew and seek our customers' support to help us create a guide-dog friendly environment," she added.
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