Last week in Prime Minister's Questions, I queried why the Government is trying to exempt London from new air quality controls, when it claimed that there would be no further expansion of Heathrow unless proposals met strict environmental limits. As usual, I was unable to get a straight answer, but I am not alone in finding this.

You may have read about the three pensioners who were stopped at Heathrow Bus Station on their way to the No to a Third Runway demonstration in Sipson.The policeman who stopped them stated that it was because they presented a "threat", pointing out that they wore anti-Heathrow expansion t-shirts.When asked why three elderly pensioners represented a threat, he apparently was unable to answer.

Parliament is still very much preoccupied with the 42 days issue in the Anti Terrorism Bill. The argument has gone to the House of Lords but will inevitably return to the Commons in the autumn. Speaker after speaker lined up to condemn the proposals and I am certain that they will be overturned there. However, with all the economic gloom around and increasing energy, food and fuel costs, not to mention the slump in the housing market and increased concerns about job security, some may ask why are we all so concerned about this one thing?

There has to be a balance. We must ensure our safety against terrorism, while also protecting our civil liberties.Counter-terrorism work depends on a number of things, but in particular on sound intelligence and good police work but not necessarily on changes in the law. However, something has gone wrong when the state is able to use its security powers to clamp down on peaceful protest.

A 15-year-old boy was recently charged for holding a banner describing scientology as a "dangerous cult" and nearer home I have heard that an over-zealous PCSO refused to let someone take photographs at Uxbridge Bus Station citing "anti-terrorism legislation". That's why I oppose the Government's plans to change the law to allow the police to hold someone without charge for up to 42 days.

I am still far from convinced that we can justify that length of detention without trial. Our civil liberties have been what distinguish us from other countries around the world.We lose them at our peril.