When is a personal opinion so offensive that it becomes morally unacceptable? This weekend former Tory leadership candidate Andrea Leadsom discovered her comments on motherhood had transgressed an unwritten social convention. The outraged legions of leader writers, columnists and Twitterati descended and by Monday she was gone. As the politics of offence, identity and rights become ever more toxic, they become equally hard to navigate and the price of transgression is ever higher. The whole Brexit debate and its aftermath have been characterised by claim and counter claim of racism, ageism and classism. We've had laws against "hate speech" for many years now, but are we too keen to create whole new categories of "-isms" to which we can take offence? If morality rests on the ability to distinguish between groups and make judgements about their lifestyles, how do you distinguish between a legitimate verdict and an unjustifiable prejudice? Why is it acceptable to say 'It's good that the President is black' but not to say 'It's good that the next President will be white'? Why is the insult "stale, male and pale" OK, but it wouldn't be if you changed gender and race? Is this about defending the powerless against the powerful, or limiting people's rights to say what they think? Where do we draw the line between policing the basic principles of equal rights and mutual respect with a capacity to judge people by what lies in their heart? Chaired by Michael Buerk with Anne McElvoy, Claire Fox, Giles Fraser and Matthew Taylor. Witnesses are Maya Goodfellow, Josh Howie, Peter Tatchell and Dr Joanna Williams.