A number of fiction books I've read recently are by lawyers-turned-into-novelists. This leads me to the non-scientific and subject-biased conclusion that it is common for lawyers to become fiction writers (not that there is much difference with legal writing--the fictional part, that is). I'll call this the lawyer-writer syndrome.
Now, there is another condition known as the doctor-writer syndrome very prevalent among medical writers. In these cases, being a physician is a great advantage for reasons I explain in Physician Career Change and Physician Career Expansion.
Some doctors are even able to go beyond the corporate careers in medical writing and become expert authors themselves--for example, writing books on current health topics for major publishers.
If you are interested in this path, there is a nice little piece of advice on David Hellerstein's site.
Thanks for reading!