These three are not just any doctors, as each is a former president of the "doctors’ union", the Australian Medical Association, a position that is a conveyor belt into political life for medical practitioners. Nelson was association president in 1993-95 before entering the federal parliament in the seat of Bradfield in 1996. Phelps was president from 2000 to 2003 and is also an elected member of Sydney City Council. Owler, known for his road safety campaign advertisements, was president more recently, from 2014 to 2016.

Other association presidents who have aimed for federal parliament include Dr Bill Glasson, 2003-05, who stood unsuccessfully for the Liberal Party against Kevin Rudd in Griffith in 2013 and again in the February 2014 by-election after Rudd’s retirement.

Their status has made them celebrity candidates because of their high public profile. That comes from the fact their function as association president has them constantly in the news. Not only is health policy, including hospitals, one of the three or four big ticket items at the centre of the Australian federal budget but health, including both physical and mental health, is relevant to many other areas of public life including veterans affairs, refugees and asylum seekers, education, drought policies and social welfare, as well as life and death issues like euthanasia and abortion.

The expertise of the association is sought on most of these issues on a regular basis, which puts the federal president and other senior office-bearers in the public spotlight. This develops them into skilled media performers as well as having the necessary organisational skills to preside over a large and complex organisation of professionals.

Seven former association presidents, including Phelps, Glasson and Owler as well as David Brand, Mukesh Haikerwal, Andrew Pesce and Steve Hambleton, campaigned together during the same sex marriage debate arguing that a "Yes" vote was necessary for health reasons. The current president, Dr Tony Bartone, has entered the debate about the children in detention on Nauru by calling their situation a humanitarian emergency.

Other groups of doctors, professional and ideological, also have a voice. As the peak body the association is surrounded by other associations, including some, like Doctors for Refugees, which want it to be more outspoken on this social issue. The association is reasonably centrist, but when doctors enter politics it is more likely to be on the conservative side, though there is usually a doctor or two in Labor ranks. Dr Mike Freelander, the Labor MP for Macarthur, worked as a paediatrician for almost 40 years before entering parliament in 2016.

There are many different types of medical practitioners so it is hard to generalise about the other skills they bring as doctors to the parliamentary and ministerial life. Some know a lot about general practice while others work in hospitals. Some are generalists while others are specialists. Owler is a neurosurgeon, Glasson an ophthalmologist, Nelson was a general practitioner with a special interest in Aboriginal health and Phelps is a specialist in general practice. Dr David Gillespie, the former minister in the Turnbull government, is a gastroenterologist. Senator Richard Di Natale, the Greens Leader, was a general practitioner with a special interest in public health.

But as medical graduates, they have all experienced a demanding university education, including science subjects, some on-the-job training and some experience of patient care. They are all a member of a caring profession. The parallels with political life are such that the electorate office work of MPs is often described as a doctor’s surgery.

With this combination of skills and experience, medical practitioners have plenty to offer in parliament. Despite this, and despite the high profile of the current crop, doctors are rarer than you might think in politics. Historically, the most prominent has been Sir Earle Page, the Country Party leader who briefly became prime minister.

There are usually only a handful as demonstrated by regular research by the Parliamentary Library. A recent report (2013) on traits and trends in federal parliament showed that among occupational backgrounds, health professionals (medical practitioners, dentists and nurses) made up only 2 per cent, four people.

Parliament is now dominated by business executives and small business owners, lawyers, political consultants, trade union and party officials. Former police and defence force members are increasingly prominent. Many parliamentarians have also boarded the political party escalator at an early age. This is a narrow band of backgrounds and as we rightly search for a more inclusive parliament, in terms of gender, ethnicity, sexuality and age, occupational background should be recognised as an equally important factor.

Owler is a long-shot to be elected. Phelps may only have a short parliamentary career. But, like Nelson, that is not the sum of their careers and contribution to Australian public life. Their presence in politics is to be commended and there should be more like them. This would help to re-balance the range of occupational backgrounds in our federal parliament.

When they get into parliament, on either side of the political divide, doctors generally bring a full life experience and wide-ranging and relevant skills to the job of representing us.

John Warhurst is an emeritus professor of political science at the Australian National University.