In yesterday’s edition of the journal Science, the geneticist Craig Venter announced that his team has created the genetic code of a bacterium. It is only a matter of time before he transplants this into a cell to create the first artificial life form. Such microbes might be created to make new antibiotics, but they also raise ethical concern. Critics worry about lethal new germs, created by bioterror or accidental “bioerror”. Some also consider it morally wrong to mould new life.

Venter’s project is one of many recent issues that turn on bioethics. Scientists this week have been contesting new consent laws that would ban many cloning experiments. The arguments about opt-out organ donation and the upper limit for abortion also have an important ethical element.

It is because of such questions that the House of Lords will on Monday debate the establishment of a National Bioethics Commission. The proposal is for a statutory body of six to eight experts in the legal, philosophical, theological or scientific issues surrounding human biology, who would advise the Government. Members would have to represent different points of view, including “the importance of human dignity and the sanctity of life”. It is strongly supported by religious leaders such as Cardinal Cormac Murphy-O’Connor.

Ethics should, of course, be considered in biology and medicine, and a statutory commission may seem helpful. However, it would be unnecessary, and the logic behind creating one is flawed.

First, government is not short of ethical advice. Within Whitehall, bodies such as the Human Genetics Commission provide guidance within their fields and, beyond it, the independent Nuffield Council on Bioethics commands great respect. A national commission would duplicate advice that is already available elsewhere.

Advocates of a commission also like to point to similar bodies run by other countries, but it is far from clear that their existence frames laws that are any more “ethical” than Britain’s. Italy has one, but it has the most restrictive IVF laws in Europe: even sperm donation is illegal. Is it ethical to deny couples a chance of parenthood?

In the US, the President’s Council on Bioethics, chaired by Leon Kass, has been packed with conservative thinkers who oppose embryonic stem cell research. Members who dissent from that line have resigned in exasperation. Its advice has been used to justify a ban on much stem cell work – though most scientists and patient groups think the ban unethical. But it has done nothing to regulate an IVF industry in which five embryos can legally be transferred to the womb. This highlights the biggest problem with institutionalising bioethics: there is little agreement on what is ethical in the life sciences and what is not.

Kass is a leading bioethicist who believes in the rights of embryos. John Harris, a noted British philosopher, takes the view that the rights of the living come first. The choice of which argument to accept depends on individuals’ political and philosophical outlooks, not on hard facts.

A national bioethics commission, particularly one that must represent all strands of opinion, is thus bound to be a hotchpotch. It would deal in nothing but disagreement, leaving politicians free to cherry-pick the arguments they like – just as they do at the moment.

Ethics is not like physics: you do not have to be an expert to have a worthwhile opinion. It does not generally deal in right or wrong answers. Its impact on public policy can fairly be settled only by political debate, never by argument from authority. There may thus be something to be said for a parliamentary ethics committee made up of MPs and peers (plus the odd bishop). But the law cannot be made more “ethical” by venerating supposedly expert opinion. In truth, no such expertise exists.

Mark Henderson is the Science Editor of The Times

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