Duplicate content across many webpages like those contained in terms and conditions which are similar in many aspects but are legally required will not hurt your website rankings in Google. However, having duplicate content on other important pages of your site that are not legally required or has scope of change may affect your website presence on Google.
Matt Cutts gave a simple explanation that legally required similar content webpages are ignored by the search engines and they do not cause any harm in the search rankings of the website. This explanation was necessary as many webmasters were confused after the Panda and Penguin updates as all kinds of duplicate content can hurt their website. It was for this reason that webmasters contacted Google to specify a valid answer to this.
Matt Cutts gave a simple explanation that legally required similar content webpages are ignored by the search engines and they do not cause any harm in the search rankings of the website. This explanation was necessary as many webmasters were confused after the Panda and Penguin updates as all kinds of duplicate content can hurt their website. It was for this reason that webmasters contacted Google to specify a valid answer to this.