Journalism, indeed society, would be all the poorer without whistleblowers. They occupy a particularly vital place in the history of the press.
Their courage in speaking up, often in the face of extreme institutional pressure, has brought to light stories of local, regional, national and international significance.
Yet everywhere you turn these days there is some authoritarian figure doing their damnedest to make sure the whistles remain silent.
Nowhere more so than in police circles. Last week Press Gazette reported the alarming story of news agency INS, whose phone records had been seized without the agency even knowing.
“They were desperate to find the identities of police officers and others they thought might be giving information to INS,” said agency chief Neil Hyde.
Meanwhile in Wales, another agency was shocked to have its offices searched for a document leaked to it about allegations of bullying at a senior level of the North Wales force.
Dee News boss Elwyn Roberts was asked to give DNA samples so that officers could identify the person who had leaked him the documents. Quite rightly, he refused, and outraged journalists across North Wales protested to Chief Constable Richard Brunstrom. His dismissive reply this week makes it clear how low he ranks press freedom on his list of priorities.
All this happens against a backdrop of a Government happy to ensure the climate of fear for those who would call them to account is near tropical proportions.
How many whistleblowers would pick up the phone to a journalist today without first thinking of the crazed molehunt that preceded the death of David Kelly? Already wracked with uncertainty and torn by the dilemmas and conflicting loyalties that tend to characterise the stories they are witness to, they have more reason than ever not to make the call.
Even Lord Hutton, who presided over the Kelly inquiry, has joined the fray by demanding to discover the identity of the person who leaked his own report, a day early, to The Sun.
This just adds to the institutional belief that anyone who speaks out of turn is to be hunted down and punished.
We have our own role to play, not just in fighting these intrusions, but also in making sure sources can trust us to stay far enough ahead of the game in ensuring that their anonymity is protected, if that is what they want.
If the phone stops ringing, if the whistles stop blowing, we’re all in trouble.