The resignation of the BBC's Director General has prompted a debate about the nation's broadcaster.  It's not hard to conclude that the BBC's management needs a shake-up and its governance strengthening.

But let's remember the root cause of these events.  The BBC suppressed a programme which would have revealed terrible misdeeds of child abuse, then ran another which directly caused false allegations to be made against an innocent man.

The problem, say some, is the internet and new forms of social media which cannot be policed.  Well, no, the problem at source was poor and deeply irresponsible journalism by a conventional broadcaster, and equally irresponsible comment that followed.

The BBC all but named the figure concerned.  That led the foolish and the malevolent to take it upon themselves to name him on the internet.

Some of those who contributed to his defamation included prominent journalists and public figures who should have known better.

The real problem is that people post messages on Facebook and Twitter without any sense that they are saying things that are inappropriate in the public domain.  Even serving police officers post abusive messages, apparently without a second thought. 

The BBC debacle comes at a time when press freedom is being hotly debated.  Lord Justice Leveson's report is expected before Christmas.  It's anticipated that he might call for some form of statutory regulation of the press, on the grounds that self-regulation has failed.

Last week 40 Conservative MPs signed a letter calling for independent regulation.  They were rewarded with a vicious character assassination by the Telegraph.  The press does not want to be constrained.

There is a powerful case for press freedom.  But we should not forget that the Leveson Inquiry came about because of abuses by the press against members of the public, including the bereaved families of service personnel and Millie Dowler.

So the question is, what will prevent this kind of thing in future?  Let's see what Leveson proposes.  But one thing is clear: regulation will not police the new media.

Today, we are all editors.  We decide what to publish with each tweet we send and each message on Facebook we post.  We don't have lawyers to consult or a regulatory body to constrain us.

Instead, we are required to exercise an old fashioned virtue.  It's called responsibility.          

Christopher N Howarth