Public art works tend to be polarizing - loved or loathed, embraced as a welcome addition to a community or resented because of the cost or the look of the work. Should the public have a say in substantial public art works, or is that a decision best left to others? Lewis Biggs has just judged the 2015 International Award for Public Art in Auckland. He is a former director of the Tate Liverpool - the city was the 2008 European Capital of Culture which saw many millions of pounds poured into its regeneration.