John Knox Political reporter, BBC Scotland

He was forced to resign after voting for an SNP motion against the renewal of Britain's nuclear weapons.

The bombshell came at the very end of term.

Poor Malcolm Chisholm was left writing his letter of resignation alone, sitting at the computer in his ministerial room on the third floor, while the rest of the building was in darkness.

It was Thursday evening. All the other MSPs had gone back to their constituencies to prepare for Christmas.

Malcolm Chisholm resigned from the government

"It is with deep regret that I found myself unable to support the official Labour position on the issue of Trident," he typed.

"In those circumstances, notwithstanding the fact that it is an issue reserved to Westminster, I realise that it is not tenable for me to continue as one of your ministers."

It all began with the SNP using their debating time on Thursday morning to stage a debate on Trident.

It was accompanied by carol singing anti-nuclear campaigners outside the parliament.

"Vote today with your conscience," the SNP's Nicola Sturgeon pleaded with MSPs.

"We want to say loudly and clearly to the UK government - think again."

It was a fairly rowdy debate but an inconclusive one.

Forced to resign

A compromise motion from the Liberal Democrats calling for the decision on Trident to be postponed was defeated by five votes.

The SNP's own motion, against renewal, fell by 72 votes to 45. Among the 45 were four Labour rebels, Bill Butler, Marlyn Glenn, Elaine Smith and Malcolm Chisholm.

It became clear as the evening wore on that Mr Chisholm had been forced to resign because he'd voted with the SNP.

Ms Sturgeon praised Mr Chisholm's "principled stance".

And she went on to point out that "only two weeks ago, the First Minister Jack McConnell told all MSPs to act with their conscience".

Trident is based at Faslane Naval Base

She added: "Now it appears he cannot stand to have anyone with integrity in his cabinet."

It was curious that there were no ministers present at the "great debate" which the nation is supposed to be having on Trident.

Mr McConnell himself had an excuse, he was ill with bronchitis.

The other ministers were busy running the country.

But by voting time at 1700 GMT, they'd finished doing that and were free to toe the government line.

It was curious too that Labour's first batswoman in the debate, Maureen Macmillan, said she'd never been persuaded Trident was a deterrent and was even less convinced now.

Drugs issue

She spoke movingly of visiting Hiroshima and Nagasaki, "desolate, compelling places".

Yet when it came to the vote, she too fell back into line.

Like the dark submarine it is, Trident will surface again and again as the election approaches on 3 May.

It will almost certainly be one of the main issues, despite the fact - as Mr Chisholm ruefully pointed out - it's got nothing directly to do with the Scottish Parliament.

Drugs have everything to do with the Scottish Parliament however.

The SNP's Deputy Leader Nicola Sturgeon welcomed Mr Chisholm support for the motion

And the fact that the number of children under 15 using drugs has trebled since 1999, from 53 to 188, so shocked Ms Sturgeon that it was her first question at question time on Thursday.

"This is not progress," she told Nicol Stephen, the deputy first minister who was standing in for Jack McConnell.

Mr Stephen shared her concern, of course, but he insisted "significant progress" was being made in tackling drug abuse.

The funding available for drug treatment had gone up from �12m to �23m.

The Conservative leader, Annabel Goldie, was "seized with unease" about the whole drugs problem.

"You are jointly and severally responsible," she told Mr Stephen.

Post offices

"For seven years of rampant drug-related crime, escalating methadone prescriptions, soaring cocaine use, the completely discredited Know the Score initiative and a political vacuum on drugs strategy."

Mr Stephen conceded that there had been "some increases" and he shared the change in public mood over methadone in recent weeks.

"There should not be an over-reliance on methadone. There should not be a single approach to drugs policy and there never has been."

There have been debates this week on rural post offices, on exactly how the executive's �31bn budget is scrutinised and on the increasing number of parliamentary commissioners, or Tsars.

There have been a couple of end of term reports from the committees too.

The chamber was told that much was being done to tackle drug abuse

The education committee said the vetting procedures in the new legislation on protecting vulnerable adults go too far and may deter people from volunteering to help.

The justice committee brought out a report asking serious questions about the executive's plans to end automatic early release.

Where would the 1,100 extra prison places come from?

How much support would there be for the 8,600 offenders serving part of their sentence in the community?

The environment committee decided to mount its own mini-inquiry into the plan to transfer oil from Russian vessels into larger tankers in the Firth of Forth.

And it agreed to keep a very close eye on the planning application for a fish farm just up the coast from Scotland's first "no fishing zone" proposed for Lamlash Bay in Arran.

Public holiday

So, the last week of term illustrated yet again the contrast between the routine work of the parliament and the big splash issues of the day.

Politics is a curious mixture of image and reality.

Looking back over the last year, our big stories have been the Forth Bridge, rows with London over "lost" foreign prisoners, "dawn raids", nuclear power and Trident, and whether St Andrew's Day should be a public holiday.

None of these resulted in substantial decisions by the Scottish Parliament. They were largely symbolic debates.

Yet, in this same year, there has been some useful tidying up work done on bankruptcy law, animal welfare and planning rules.

A ban on smoking in pubs came into force in 2006

You could argue too that some improvements have resulted from the debates over NHS waiting times, free personal care, youth offending and the drug problem.

Certainly the executive has been put under pressure to act.

But actually, the thing the Scottish Parliament is most famous for this year is the ban on smoking in public places.

Yet, it was hardly discussed, the legislation was passed last year.

It came into effect in March this year and has transformed the image of the parliament.

Finally people can answer the Life of Brian question, "What has the Scottish Parliament ever done for us?"