At a place called Clowntown where many children spend their birthday parties, singing “Happy Birthday” is illegal. A British father was celebrating his daughter’s birthday at the popular party place in London when the staff called the cops on him for singing Happy Birthday.

The head-scratching incident occurred when heating engineer Colm Doherty, 47, was celebrating his daughter Cara’s eighth birthday at the play centre in Muswell Hill. It was supposed to be a merry celebration, but because they did not have prior “birthday package” reservation, they were told what they were doing, which was simply celebrating a birthday, was against the place’s policy.

His wife Marie, 49, had contacted Clowntown to try booking a birthday party package for 20 children and six adults. However, she was told that there was no availability. The family decided to visit the centre anyway.

And when they did, they noticed that two “party booths” were vacant so they asked a female staffer if they could use one. After being given a go signal, they proceeded to spend over £300 [A$492] on food and entrance fees for them and their guests.

However, the female staff later told them that she was “in fairly big trouble” for allowing them the use of the room when they had no reservation. She also warned them not to “produce a cake or sing happy Birthday.”

But the Dohertys did produce a cake in accordance to the company’s “You bring the cake, we do the rest” motto. They did not eat it on the premises, though; they just lit the candles and sang happy birthday.

“When the cake came out you could sense a bit of nervous tension among the staff, and one particular lady came storming down and told us that we could not sing and to put the cake away,” Mr Doherty told the Daily Mail.

He stood in front of the staff member to shield the children and told her to go away, adding that he was left in “shock and disbelief” by the Clowntown staff’s actions.

The staff member called the police, with manager Ian Slanzenger telling the paper that Mr Doherty displayed an “aggressive attitude” when the father pointed his finger at the staff member’s face and took photos of her.

Mr Doherty denied being aggressive, explaining that he only took the picture of the woman who tried to stop them from singing Happy Birthday so he could identify her when he files a complaint later.

The overzealous Clowntown manager also claimed that the group were offered a birthday package but chose not to take it, although he admitted that they spent more on food and entry fees than they would have if they took the package.

“You don’t celebrate a birthday party on our premises unless it is the package you obtain,” Mr Slazenger insisted. “There were four other groups and we did not want them to see that people can just come in and celebrate a birthday without respecting our policy.”

In a radio interview with LBC 87.3’s James O’Brien, the manager said that Mr Doherty claimed that they came to the place and lied that they were not there to celebrate a birthday.

When the DJ asked what the fuss was about with the family not booking a birthday package and bringing a cake if they would be required to bring a birthday cake anyway if they had booked a party package, Mr Slazenger maintained that it’s their policy.

Hear the Clowntown’s side of the story here:

listen to ‘Police Called Over Row Over Children's Birthday Cake’ on Audioboo

The police were given CCTV footage of the incident and had spoken to Mr Doherty, but decided not to take formal action against the father.