The papers have recently been plastered with pictures of Kate Middleton taking on her first 'charitable' work as a Royal. The kids doing art next to her look almost as happy as the readers looking at them, so what's not to like?

Helping charities is obviously a good thing to do - people who do it deserve credit. Volunteering is, though, meant to be unpaid: that's part of what so valuable about it. People who volunteer their time to help others deserve more credit than people who get paid to do it. So which category does Kate Middleton fit into? The 'volunteer Kate' deserves massive credit for giving her own time, unpaid, to promote art and help people. The 'paid Kate' deserves less credit because she's just doing her job.

Looking at recent media coverage of her charitable work, you'd guess it's 'volunteer Kate' that we're all admiring. Reading the same papers over the past year, though, you'd hear about 'paid Kate' instead: one of the main justifications for all of the Royals receiving taxpayers' money is that they do charitable work. In other words, they're paid for it.

That means we need to make a choice. If one of the reasons for the Royal Family getting public money is that they help charities, then they shouldn't get credit for 'volunteering' the time we pay for. If they don't receive our money to help charities then they deserve credit for volunteering but we can't keep justifying their existence on grounds of charitable work.

Of course, Kate Middleton's a total novice when it comes to charities. The Queen is patron of over 600 charities, most of which she didn't choose but simply inherited. Similar numbers apply to other high profile royals, and although it's our money that funds this patronage we don't, apparently, have any say in which causes they support. Many people would agree that most of these charities do valuable work supporting people with osteoporosis, cancer and various disabilities.

Not all of them are quite so popular though. Prince Charles, for example, uses his time and publicly-funded position to endorse one of the oldest surviving hunting clubs in the country (Tarporley). That wouldn't be a problem if he was volunteering his own time (and a name built up through his own work) to endorse a hunt, but anti-hunting campaigners might wonder why they should stump up the cash to allow him to.

The same questions might arise with Kate Middleton. At the moment she's patronised causes that few people have problems with, but that might change. If our money pays for patronising hundreds of charities then shouldn't we have some say in which causes are endorsed?

Royalists have confused this question by using charitable work to justify an institution that we all pay for through our taxes. To be clear, we need to find out what we do and don't get for our money. We can have 'volunteer' Kate or 'paid' Kate, but not both. Choosing between the two might help us see what - if anything - the monarchy is for.

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