The Guardian’s two jobs jibe is a bit lame and unoriginal – the prime minister, the leader of the opposition, the opposition chief and deputy chief whips, and every government minister in the Commons has another paid job that to some degree may distract him or her from their role as a constituency MP. But no one is suggesting that they should not be both ministers or shadow ministers and MPs. Working hard and managing one’s time are what busy people do and in government and out of government and in my work as a barrister I have been able to do just that. Certainly no constituent has ever said I have failed to look after them because of my work at the bar or as a minister or shadow minister, and many constituents seek my help precisely because I am a practising barrister.

It is essential that the Commons, and thus the frontbench teams in both government and opposition, is not reserved just for professional politicians without experience of the world outside Westminster and student politics. Policymakers and legislators should be informed by experience in areas such as business, farming, journalism, medicine, teaching and lecturing, the law, industry, trade unions and the charity sector. Parliament is the better for having MPs who do not spend and have not spent their whole time inside politics.

It was no secret to my constituents when I first stood for parliament in 1992 that I was a practising barrister of many years’ standing specialising in media law. I used to work for the Guardian among several other publishers and broadcasters; it was no secret at each of the following general elections and it will be no secret at the next. It was presumably why two Conservative party leaders, William Hague and David Cameron, selected me to be shadow attorney general and why Cameron also appointed me as shadow home and then shadow justice minister, and why he, as prime minister, asked me to be solicitor general. And it may be why so many politicians from all parties in both houses of parliament ask for my advice about defamation, privacy and other legal matters, and why Lord McAlpine asked me to act for him in his libel complaints, one of which involved the wife of an MP.

I believe that I have been a better scrutiniser of legislation, and designer and developer of public policy, because I have kept my legal practice going; my paper Prisons with a Purpose 2008/9 was informed by my experience as an MP, barrister, crown court recorder and part-time judge. Just this week I made a speech in the Commons on the social action, responsibility and heroism bill, and last week I asked a question of the attorney general. I have a better understanding of the channels of communication between government and the Commons on the one hand, and the senior judiciary and the legal profession on the other, through maintaining my practice.

That I have been able, since leaving government in September 2012, to successfully re-establish my practice as a lawyer in addition to doing my work as an MP (as well as assisting the Samaritans), demonstrates the strength of the system, not its weakness. If others are not qualified to do anything else or do not have the stamina or organisational and time-management skills to do more than one thing at a time, it surely does not mean that they should prevent others who can and do from doing more.