Though he was on the party's economics team for the last five years, Mr Smith maintained his green links as president of the Socialist Environmental Resources Association (SERA) and on a more personal level as an active member of groups dedicated to preserving wild land in Scotland.
Thumbnail sketches of the 41- year-old member for Islington South and Finsbury invariably note that he is the only MP to have climbed all 277 hills exceeding 3,000ft in Scotland - the 'Munros' - and the only one to have declared his homosexuality openly.
Mr Smith's leap into the Shadow Cabinet at equal-sixth place in last week's ballot, after coming nowhere at two previous attempts, appears to have confounded those who thought his 'coming out' at a gay rights rally in 1984 would blight his career.
'Effectively I have said, Yes, I'm gay, so what? Now let's get on with the business of being a politician,' he told the Independent. 'Perhaps recent events confirm the wisdom of that honest approach. Unless double-dealing, or hypocrisy, or treachery of any kind are involved then you should not make a meal of it.'
Had John Smith been choosing a real Cabinet, Chris Smith would be Secretary of State for Environmental Protection while Jack Straw would be Secretary of State for the Environment (Local Government and Housing), each with his own ministry. Though the new green spokesman has made his mark with adept handling of complex taxation and economic detail, his acadamic background, by contrast, is a double first in English from Cambridge and a PhD in 18th and early 19th century poetry. He entered the Commons in 1983, wresting his seat from the SDP after five years on Islington borough council.
Setting out his priorities, Mr Smith said he would be harrying Michael Howard, Secretary of State for the Environment, on issues such as reductions in carbon dioxide emissions; ensuring environmental considerations are central in Labour economic policy making; and developing an environmental charter of rights.
This last, still in the ideas stage, would make it easier for people to challenge industries polluting with fumes or noise; perhaps first through an ombudsman and persuasion, and then by legal action.
'About three years ago the environment shot to the top of the political agenda for a very brief period, yet at the April election it hardly rated as an important issue. I want to see it moving back up the agenda,' Mr Smith said. 'There has been a tendency in all political parties, except the Greens, to regard the environment as something separate, something out of the mainstream of political life, that had to do with holes in the ozone layer, access to the countryside and saving the whale.
'I want to see the Labour Party putting environmental concerns at the heart of its appeal to the electorate at the next election and I know that the public shares a lot of that concern.'
Mr Smith said he would be talking to Gordon Brown, the shadow Chancellor, 'fairly early on' about devising methods of measuring national growth that took into account depletion of natural resources and other environmental consequences. 'The most obvious example is North Sea oil; the more we extract the better our GDP does, but that ignores the fact that you are removing one more barrel of a finite resource.'
He wants the pounds 1bn a year subsidy which electricity consumers pay through their bills to the nuclear industry transferred to cleaner technology for fossil fuel burning and research into renewables such as wind, wave and solar power. He will be pressing Mr Howard over the creation of an Environmental Protection Agency at arm's length from government, and over compliance with EC water quality standards.
Closer to his heart, though less likely to be realised, Mr Smith would also like to see 'the ordinary people of this country granted a right of access to open mountain and moorlands'.
As well as being a member of the socialist climbing club, Red Rope, Mr Smith is a member of the Scottish Wild Land Group and a trustee of the John Muir Trust which has bought mountains in order to protect them. It is an enthusiasm he shares with his party leader, whom he has accompanied to the top of a string of Munros.
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