This is a favourite question for public service jobs and is designed to check two things. The first is that your understanding of the world is wide and up to date, and the second is to see what sort of political attitudes you have. It therefore makes sense to read a quality daily newspaper thoroughly for at least a week before any interview. This is particularly relevant when you have applied for a job where you would be representing the views of the employing organisation to other agencies or clients.
Employers rarely want candidates to express strong political views in interviews. This is certainly true of the Civil Service, not-for-profit sector and local authorities. Ideally, you should illustrate that you know about a current issue in some depth, you are aware of the two sides to the argument, you can understand the feelings on both sides, and you realise what a difficult political problem it is.
Politics should be left to politicians, or to any of us in our private lives, not brought into the workplace. If you are asked for your opinion on a political issue, refrain from coming down heavily on either side. Government or local authority employers want to be sure that you are aware of the need to put into practice the wishes of the political leaders of the day – and they can be right or left wing.