In my diplomatic career, I spent a great deal of time assessing the democratic merit of elections in various countries abroad. That gives me a peculiar perspective in looking at elections in the UK, and wondering what a foreign observer would make of them. I can do this also with the insight of having twice run as an independent parliamentary candidate.

Against international standards, British elections leave a great deal to be desired. The first crucial failing is the lack of an independent administration of the elections. In each constituency, the election is not run by the Electoral Commission, but by the local authority. The national Electoral Commission has only an advisory role and cannot even monitor or instruct local returning officers. The returning officer is almost always the chief executive officer of the local authority.

The problem is that, de facto, those chief executives are party-political appointments. Particularly in the long-term New Labour rotten boroughs of the north, local government appointments are a New Labour nexus. Bluntly put, the New Labour council of a northern town is almost never going to appoint a Tory chief executive.

In fact, the lines between council appointments and party appointments are often blurred. Bill Taylor was Jack Straw's agent and full-time organiser in Blackburn in 2005. His pay came as a youth organiser for a neighbouring New Labour-controlled council. It would have been illegal for him to be thus employed by Blackburn itself and to campaign in the constituency. Reciprocal agreements between New Labour councils to provide full-time party staff – at the council taxpayer's expense – are not uncommon.

There was a time when honesty in public life was such that the party allegiance of a local authority and its staff would not affect confidence in its ability to conduct a free and fair election. The parliamentary expenses scandal has killed the myth that our politics are honest and well motivated. I do not accept local authority chief executives as genuinely independent returning officers.

I will continue to use Blackburn as an illustration, because I have an intimate knowledge, having stood there in 2005. An independent candidate standing against Jack Straw in the coming election, Bushra Irfan, has already been told by the local election office that she will not be able to exercise her right to place her own seals on the ballot boxes, as the hasp only has room for the council's seals.

She has just erected an election banner on her own property. Within hours, council officials arrived to dismantle it on the grounds that it did not have planning permission. This ignores the fact that election advertising for a "pending election" is specifically exempted from need for planning permission. But aside from that, one wonders whether other planning issues in Blackburn draw the same instant hit-squad response from the council?

Postal voting is a further major area of concern – and again, that concern principally centres on the northern cities. New Labour deliberately brought in a massive expansion in the use of postal voting, which was previously available only to the infirm or to those with other legitimate reason for not making it to the polling booth.

The polling booth is the vital question here. Those bits of board that prevent anyone from seeing how you vote, are an essential element of the secret ballot. New Labour has, in effect, deliberately removed it. Any vote made at home is a vote that may be filled in under the coercive eye of an individual able to enter your home and intimidate you – something nobody can do in the polling booth.

I am not theorising. Particularly among some patriarchal Asian communities, community leaders and heads of extended families can and do demand to see the postal ballot of those under their sway, before it is posted. Belated "safeguards", like having to sign the accompanying form, do nothing to stop this domestic intimidation. It is widely recognised that one result of this postal ballot system has been the effective disenfranchisement of hundreds of thousands of Asian women. Just as bad, it has also disenfranchised lower-status men in many Asian communities.

Again, I speak from experience, having listened to many first-hand accounts from intimidated people in Blackburn – and, in every case, the intimidation was to vote New Labour. In the Blackburn constituency in 2005, an incredible 12,000 postal ballots were cast: that represented 29% of the vote, compared to a national average of under 13%. What does that suggest?

But it is still more blatant than that. You will find this next fact astonishing. The regulations have been designed specifically to prevent the exposure of postal ballot fraud. By law, the postal ballots have to be mixed undetectably with the polling booth ballots before they are counted. Therefore, there is no way to prove if, as I suspect happened in Blackburn, a candidate received 25% of secret ballots but 80% of postal ballots.

It is this compulsory destruction of the voting evidence that convinces me that the motivation for extending the use of the postal ballot can only have been a self-serving act by the New Labour government.

But there is a still more fundamental point, which raises doubts about the democratic validity of Britain's elections – and that is the question of whether a real choice is being presented to the voters.

International electoral monitoring bodies pay a great deal of attention to this. For example, in December's parliamentary elections in Uzbekistan, it was the lack of real choice between five official parties, all supporting President Karimov's programme, on which the OSCE focused its criticism.

How different is the UK, really? For example, I want to see an immediate start to withdrawal of British troops from Afghanistan; I am increasingly sceptical of the EU; and I do not want to see a replacement for the vastly expensive Trident nuclear missile system. On each one of those major policy points, I am in agreement with at least 40% of the UK population, but on none of those points is my view represented by any of the three major political parties. And remember, only those three major political parties will be represented in the televised leaders' debates that will play such a key part in the election.

Those debates will take place between three representatives of a professional political class whose ideological differences do not span a single colour of the wider political spectrum. Voters in Wales and Scotland are luckier, but for most people, there is little really meaningful choice available.

The Lib Dems are the nearest most people have to a viable alternative. At the last election under Charles Kennedy, they reflected public opinion in opposing the Iraq war, but under Nick Clegg they have become less radical than at any point in my lifetime.

The media limitation of debate to a narrow establishment consensus is not merely a problem at the national level. When I was a candidate in both Norwich North and Blackburn, the BBC broadcast candidates' debates, but on each occasion I was not allowed to take part – even though I was a candidate – because the BBC was terrified their audience might hear something interesting. The Electoral Commission specifically recommends that all candidates be invited to take part in all hustings and candidates' debates – but the Electoral Commission is a paper tiger with no powers of enforcement.

Censorship extends far beyond that. A traditional feature of British elections is the electoral communication, under which each candidate can send out a copy of their electoral address, delivered to every voter free by Royal Mail. Under another bit of Kafka-esque New Labour legislation, the Royal Mail now vets the content of every electoral address. The text must be seen and approved by a central Post Office unit before the leaflet can be printed and prepared for delivery.

So much for freedom of speech. The New Labour rationale for this is that the Royal Mail is checking the candidates' election address does not fall foul of Britain's notorious libel laws – the harshest and most restrictive of any western country. It also has to be cleared for many other laws restricting free speech, many of them introduced by New Labour – for example, that it does not "glorify" terrorism, or incite racism or homophobia.

So, if a candidate were to say in their election address that they believe Tony Blair and Jack Straw are war criminals, or (to take a topical example) that Christian bed and breakfast owners ought to be allowed to refuse gay couples, then their election address would be locked by the Royal Mail.

This is crazy. The Royal Mail delivers millions of letters every day. Some of them doubtless contain libellous and even racist statements. The Royal Mail does not open them all and check they are "legal".

Actually, whisper that softly, we don't want to give New Labour ideas.

Furthermore, in this case, it is not a court that decides if a statement is libellous, it is the Royal Mail. This is censorship of candidates during an election and without any court injunction. It says yet more about the cosy establishment clique that governs us that none of the major parties is up in arms about this.

Now, we come to the most fundamentally undemocratic aspect of British elections: the electoral system. It delivers massively disproportionate results with minority parties virtually unrepresented in parliament. At the last election, it delivered a good majority to an unpopular Tony Blair, even though New Labour received only 36% of votes cast – which represented just 22% of those entitled to vote.

But it does not favour the big parties evenly. New Labour can get a working majority with 34% of votes cast, while the Tories need 39%. If New Labour and the Tories both got 36%, New Labour would probably have almost 50 more seats. The Lib Dems could get 34%, yet win under half the seats that New Labour would get with the same percentage.

On top of which, we will see the irony of politicians rejected by the electorate being given comfy, paying seats in the House of Lords.

So, there we have British elections today: an unfair electoral system, censorship of candidates' electoral addresses, little real political choice for voters, widespread postal ballot-rigging and elections administered by partisan council officials in a corrupt political climate.

Don't be surprised if New Labour do that little bit better, when the votes are counted, than you might expect. As Joseph Stalin said, it is not who votes that counts, but who counts the votes.

So are British elections still free and fair? If this were a foreign election I was observing, I have no doubt that my answer would be no.