Should demonstrations in Parliament Square be restricted?

Julian Lewis, MP for New Forest East and a Shadow Defence minister, has posed an important question about the demonstration in Parliament Square:

"Dr. Julian Lewis: To ask the Secretary of State for Environment, Food and Rural Affairs pursuant to the written answer of 21 July 2008, Official Report, column 748W, on noise pollution, whether the repeal of restrictions on demonstrations in Parliament Square will result in (a) permanent encampments and (b) unrestricted amplified broadcast noise being permitted. [228445]

Huw Irranca-Davies [holding answer 20 October 2008]: The Report of the Joint Committee on the Draft Constitutional Renewal Bill, published on 31 July 2008, included a number of recommendations on the Government's proposals to repeal sections 132-138 of the Serious Organised Crime and Police Act 2005 which pertain to demonstrations around Parliament. The recommendations of the Joint Committee addressed both permanent protests and noise nuisance and the Government will be responding imminently to the Report."

This is a tough one for a Conservative. Freedom of speech is important to us, but so is the maintenance of public spaces. Parliament Square has been a frightful mess for years. It wasn't much fun when inarticulate commentary was blasted through a megaphone. What about the rights of the rest of us to enjoy a national landmark?

The May Day anti-capitalist marches (populated by halfwits who think that trade restrictions are anarchic) caused shops to lose thousands of pounds as the streets were unusable. Trafalgar Square saw some extremely ugly and threatening banners when extremists gathered there.

And yet people must be allowed to speak out, and surely the perceived merits of their arguments shouldn't be the determining factor. So what restrictions should be put on the right to protest?