He is the director of the University of Otago Centre for Theology and Public Issues, which has, in recent years, organised scores of public discussions on a wide range of topics, including voluntary euthanasia and child poverty.
Prof Bradstock gave a talk this week on ''public debate on bioethical issues'' as part of a seminar series hosted by the university Bioethics Centre. There was a ''hunger'' in the community to discuss serious issues, such as assisted dying, he said.
But the loss of public service television meant programmers were now mainly concerned with ''attracting advertising and therefore maximising ratings'' and ''very little time is given over to serious discussion of current affairs''.
Even programmes billed as current affairs were often ''quite lightweight'', and mainly aimed to entertain.
When the Otago centre began organising public discussions more than four years ago, he had initially been anxious about how they would go.
Some topics had attracted more people than others, but, overall, the talks had been consistently popular and many were now being ''livestreamed'' on the internet by Otago University.
A discussion on ''assisted dying''organised by the centre last year attracted 300 people, as well as television and radio coverage.
''Attendances at our public forums suggest we have a role to play and that there is an appetite for serious, informed, balanced discussion that goes beyond sound-bites and doesn't seek always just to entertain.''
New Zealand faced many ''important issues and challenges'', including ''child poverty, climate change, crime, review of MMP, economic inequality'', but informed debate was ''at a premium''.
And good debate was ''hugely important'' in bioethics, where ''myths and fears abound'' and where individual cases involving genetic engineering or assisted dying were sensationally reported but less attention was paid to disseminating reliable information and ''stimulating serious reflection''. Prof Bradstock also highlighted the importance of ''public theology''.
This could ''prompt us to ask uncomfortable questions'', including about ''the core values upon which we build our lives, our communities, our nation.''