We know democracy is deeper than elections. We should honour that.

The House of Lords needs changing. But does it need this particular reform? Labour pledged this week that it will back Liberal Democrat proposals for an 80 per cent elected chamber. There are five reasons why the left might not think this is such a good idea.

1) Elections are not always and everywhere good. There are certain advantages to having legislators that are insulated from polls, Twitter tidal waves and yes, even voters. Experience demonstrates it breeds conviction politics. Whips are less of a threat, and amendments are more likely to be introduced and won. Significant changes - including blocking the government's attempts to limit trial by jury - have been won by the Lords. The welfare and NHS legislation is just the latest example.

Even if you agree with the principle that Lords should face the electorate, the current proposals would only allow future Lords to serve one term for fifteen years. As Lord Dobbs points out, this means that they will never be subject to genuine electoral accountability. When you can't get re-elected, you may as well do what you were going to do anyway.

2) You shouldn't look at how to design a chamber until you've decided what that chamber is for. At the moment there are whole bunch of unanswered questions. As Jesse Norman astutely points out (£), it makes no sense to consider the issue of electing the House of Lords before we've resolved devolution in Scotland. Who exactly will be governed by the House, and how? Do we want the Lords to be a pool of specialist knowledge providing scrutiny as it does now, or do we want a stronger check on an executive that is often criticised for having too much power, making us more like the US?

If electing our Lords really does give the second chamber more legitimacy, then power will be more dispersed and that may well result in more paralysis. People are already frustrated with governments for not being different or radical enough. With a rival second chamber, this may well get worse. What if the left wanted to come in and set up a universal care service? Or pursue more meaningful devolution? Radical agendas will almost certainly be harder to implement.

3) Ironically, we may see a decrease in diversity. Think of disabled peers like Baroness Jane Campbell. It is much harder for them to fight and win an election than it is to get an appointment. Similarly, we can say goodbye to crossbench MPs and the valuable independence they bring. To get elected to the Lords, you'll have to be a member of a political party - and presumably we'll be presented with candidates who couldn't quite make it to the first chamber.

Democracy is about a lot more than being able to vote. One of the most common criticisms of politicians is that we come from increasingly homogenous backgrounds, turning politics into a career rather than a service. Standing for election often requires wealth. Increasingly you have to be in a position to offer free labour through internships and live in London. Right now the Lords is relatively diverse, at least in terms of experience. If we create an elected second chamber without addressing who stands for election and how, we can expect more of the same.

4) Lords reform is not the public's priority right now. No one talks about the constitution on the doorstep. People are worried about their jobs, their homes and their families. We've already had the AV referendum - spending our time debating technical legislation may look like more navel gazing, especially when the Lords are relatively popular. Research by Meg Russell at UCL shows that the Lords were held in higher esteem than the Commons even before the expenses scandal broke. Shaking it up risks making politics look less relevant, not more.

5) It may hand a huge amount of power to the Liberal Democrats. If the second house became more significant, the LibDems' role as kingmaker would become even more important. And let's not forget that this whole programme is their deal anyway. As Andrew Neil points out, Lords reform is their prize for supporting the Conservative's constitutional boundaries that damage Labour.

Hereditary peers are embarrassing, but what if we could find some way of making appointments with legitimacy. What if we had a chamber that was picked to be more representative - the head of trades in industry, charities, our leaders in art, business, and education. That would bring the wealth of British experience to the table in decision making, whilst preserving a distinctive second chamber that didn't rival the first. The public already believes that legislative scrutiny and listening are more important than votes. We know democracy is deeper than elections. We should honour that.

Rowenna Davis is a journalist and author of Tangled up in Blue: Blue Labour and the Struggle for Labour's Soul, published by Ruskin Publishing at £8.99. She is also a Labour councillor.