Last week the 40-year-old Home Office minister claimed that 'while the church spends its time discussing social issues, such as housing, politicians are left to talk about the importance of the difference between right and wrong.'
According to one Whitehall veteran, the explanation is simple: 'He said what he did because he believes it - and will not have done a lot to burden himself with research to verify it.'
This natural bluntness was revealed by the Independent on Sunday which reported contents of a leaked first draft of a speech on law and order which was toned down drastically by officials. In his original speech, Mr Maclean wanted to say that 'vermin' should be driven from the streets, to praise vigilantes, and to condemn the justice system his party has presided over for 14 years for 'being on the side of the criminal'. All in all, it is surprising that we have not heard rather more of him.
Mr Maclean was born in 1953 on Scotland's east coast Black Isle. His father worked the family's prosperous potato and cattle farm (now run by Mr Maclean's brother) and the family was part of the Free Church of Scotland.
He tells friends that he spent a large part of his first eight years in church, but that he is no Presbyterian zealot; he seldom talks religion and his wife is a Roman Catholic. His view of the Church of England and its bishops is rooted firmly in the Thatcherite era of constant friction between Prime Minister and Archbishop of Canterbury. 'For a long time,' said one Tory, 'he has been fairly contemptuous of the church's moral leadership.'
The intervention by Mr Maclean marks a departure because such criticism has come usually from the High Church or Roman Catholic element of the party - John Gummer, Ann Widdecombe or John Patten - rather than from Presbyterians. The incident, however, probably reflects Mr Maclean's right-wing instincts and dislike of wishy-washy liberalism, rather than biblical conviction.
Educated at Fortrose Academy, a highly-regarded state school, he went on to read law at Aberdeen. At school he joined the Young Conservatives, becoming founder chairman of the Black Isle YCs in 1969. In 1975 he joined Securicor where he became a group training executive.
He was also an enthusiastic Territorial Army officer in the 51st Highland Volunteers, which perhaps explains a rather military manner.
He contested Inverness, Nairn and Lochaber (Sir Russell Johnston's seat), before winning Willy Whitelaw's seat in a by-election in 1983.
Typically of the 1983 Tory intake, Mr Maclean's politics are Thatcherite - in his case more from the authoritarian, rather than the free-market libertarian, Right. He is a 'hanger and flogger' and a member of the No Turning Back group of Thatcherite MPs and ministers. Among kindred spirits, and in some quarters of the left of the Tory party, he is popular - 'a man to go into the jungle with'.
Mr Maclean has impressed himself little on public consciousness because of the jobs he performed. First came the whips' office where he spent two years. Here he helped pilot radical education reforms through the Commons.
From the whips' office Mr Maclean was moved to the Ministry of Agriculture, Fisheries and Food and a Parliamentary Under-Secretary's job that had a low profile outside rural communities. After the election, Mr Maclean became a minister of state for the environment, provoking the fury of conservationists by calling for an 'open season on Canada geese - and a few good recipes'.
Last week's incident is unlikely to hamper his career. In his Borders constituency home last week Mr Maclean received many messages of support. John Major has not spoken to the minister about the speech. Nor is his boss, Michael Howard, the Home Secretary, who was also his immediate superior at the DoE, likely to cut up rough.
One friend said: 'Howard asked for him to go to that job. He would not have taken him if their relationship was not close enough to back him in this sort of situation.' Another argues that, at the Home Office, Mr Maclean is a positive force who 'creates a lot of activity and ideas, some of which fall by the wayside and some of which become policy'. Last week's row showed the political downside of the ex-Territorial's habit of shooting from the hip.