It is hard to imagine John Singleton, advertising and talk radio boss, gambler and quintessential Aussie, as a culture vulture. But not only is he serious about bidding for a fourth commercial TV licence if a Labor government, if elected, sticks to its word and puts one up for grabs in 2006, he also wants the fourth network to show only Australian programming, with a heavy - but not total - emphasis on "culture".

Singleton laughed when I asked him recently whether horse-racing, one of his great passions, might also find a place between the operas and the ballet. Perhaps his mate Bob Hawke could be one of the resident tipsters?

Singleton, along with Sam Chisholm, who made Kerry Packer’s Nine Network the powerhouse of Australian TV and is now chairman of Foxtel, and Peter Faiman, formerly the big-event production genius at Nine and most recently at Rupert Murdoch’s US networks, are the public faces of a group that has declared it will bid for a fourth commercial TV licence if one becomes available. Other bidders are likely, perhaps even Murdoch’s News Ltd if the cross-media ownership rules are relaxed.

But despite Singleton’s public campaigning in the past 10 days, two questions remain. Do we need it? And if a fourth licence is issued, what should it show? There are no easy answers. The existing commercial networks - Seven, Nine and Ten - contend that there are not enough viewers in Australia, not enough advertising dollars and not enough programs to carry a fourth network. But they would say that, wouldn’t they? For much of the past half-century, a commercial television licence has been a licence to print money.

Yes, we do have a small population spread over a huge area, which makes delivery of television services a costly exercise. And yes, pay TV is eating away at the free-to-air audience and the advertising pie. Between 10 and 15 per cent of all TV viewing in Australia is of pay TV, depending on the time of day. So, the free-to-air networks are under attack and the value of their licences is being diminished.

Where their argument falls apart is when it comes to programs. It is wrong to say that there are not enough quality programs to fill the schedules on a fourth commercial network. Tell fans of shows such as The Amazing Race, Six Feet Under, Smallville, Third Watch and Monk, among many others, that there is not room for another network, when they have to wait for the non-ratings period over summer to see their favourite shows. Tell sports fans that there isn’t room for another network when time cannot be found on existing free-to-air TV for sports such as men’s basketball, horse-racing, and even most overseas tours by the Australian cricket team. Tell culture vultures - like, apparently, John Singleton - that they are well served by free-to-air TV. They will laugh in your face. Even the ABC has downgraded its involvement in the arts. The best of the arts is on the Ovation pay TV channel.

And then there is the argument about there being a finite amount of advertising revenue. If a fourth channel enters the market, the share of total advertising revenue available to the existing networks would drop, the networks say, limiting their ability to maintain spending, particularly on Australian programs, which can cost as much as $500,000 an hour, compared to $60,000 for an hour for American product. It’s a good argument, but it relies on the assumption that a fourth network could not serve a niche audience, for which some companies might increase their total advertising expenditure to gain access.

So, the jury is out on whether we need or can justify another commercial channel. But if there is to be one, what should it show? Singleton says it should be a limited licence, restricting its holders to showing only programs made in Australia. Some, in the past, have suggested that it be a family channel, showing only programs that reflect good old-fashioned family values. No violence. No four-letter words. No profanities. Others have opted for a gay channel, a sports channel, a comedy channel, a channel for the under-served over-50s, or a news channel.

The problem with most of those suggestions is that they already exist or, in the long term, belong on pay TV. Some niche markets are so niche in character that the high cost of operating a separate terrestrial national network, with stations and transmitters in every capital and major provincial city, could not be justified.

But there is Singleton’s all-Australian idea. I don’t know that an hour each night of Sydney talk-radio presenter Alan Jones doing a Larry King-style interview show (as Singleton alluded to), would be welcome, but Australians love to watch themselves on TV. And an all-Australian channel with everything from sport to lifestyle to telecasts of the Woolamakanka light opera society’s production of The Mikado might just work. It certainly would be different.