Your subject is...

Luckily there is a plethora of candidates, living and dead, available for a legal biography; learned luminaries who have made a major contribution to the academic, philosophical or practical aspects of the profession.

So how does one make a choice? The secret lies in personal chemistry. Something in the potential subject's life sparks off a response in the would-be biographer.

If the chosen subject is still living, there are possibilities for personal interviews and reminiscences from colleagues. If the subject died some time ago, there can be a search for papers, memoranda, background information and books written by contemporaries.

The law reports of cases in which the subject appeared or adjudicated upon must be studied. A publisher or agent may have made a direct approach. This should not be turned down as publishers willing to accept legal biographies may be hard to find.

Practicalities: how much has already been written? Will the author or holders of the copyright of this material have to be tracked down for permission to quote from it? In any event the 400-word length fair-dealing limit may apply, with due acknowledgments. Better still, the author of the sought-after material may have been dead for 50 years, in which case no permission is required.

To the enthusiast, the research is all. Nothing is more rewarding than the tracking down of a former contemporary or little known relative, unpublished memoranda or letters. However, the manuscript collections of the specialised libraries are best approached after digesting a reliable, basic book (eg 'Lives of the Lord Chancellors' R F V Houston. Clarendon Press 1964).

The right atmosphere is also important. This can be achieved by visiting the birth-place, the school and university, the particular Inn of Court, the chambers and the tribunals. In any of these places one might discover a hidden plaque or painting.

Not all libraries are dusty, but each has a highly individualised system of reference, coding and filing. Prior permission is the least of the hurdles to overcome. Arriving - with pencils and sharpener, regulation size handbag, writing pad - at a hitherto unknown destination, is a recipe for intimidation. I was not quite prepared for the kindness and helpfulness of the librarians and archivists who lay their treasures on your desk.

A matter of choice, of course, but I prefer to write with a co-author. Douglas Martin, formerly of the Lord Chancellor's Department, and I have written together on legal matters for many years. We now meet together every two or three weeks. Sustained by coffee and cakes, we can have endless discussions on our progress, mulling over what we have discovered and written so far without boring anyone else.

After the writing; the typing. Then the re-writing and the retyping follow. At last, the corrected, absolutely final draft has to be delivered to the publishers. Perhaps one last relevant source for our biography of Lord Haldane might have emerged if only we had waited a little longer. Regretfully last week, tied up with red tape and in a strengthened carrier bag, it was delivered to the publishers with mixed feelings of relief and regret. Some consolation for the loss we have sustained lies in the discussions and negotiations for the next project.

Her Honour Jean Graham Hall LLM is a former Circuit Judge.