It was handwritten, which is a little unusual for the anonymous ones. They tend to be typed and unsigned.

The handwriting was large and not unattractive. It looked like the handwriting of someone who went to school back in the good old days when children were taught cursive writing and had to keep words within black-lined cards.

The writer seemed to be having a go at me. There was no "Dear" at the start. Just "Joanne". The person couldn't believe I hadn't written about an issue involving the Catholic Church and a restructure described as a "money grab" involving schools.

"Parents haven't got a clue," my anonymous informant wrote. "Can't believe it hasn't made the press somewhere."

I've received plenty of letters like this over the years. When I first started writing about institutional child sexual abuse in June, 2006 - and hasn't that 13 years just flown by - the anonymous letters from Catholic Church people were divided into two.

There were the abusive ones that questioned my integrity, honesty, decency, legitimacy, skills, sexual history - the word "slut" was used, once - and general right to live on this planet. Then there were the other ones, always anonymous, describing horrors from the past, suicides and tragic events, and naming alleged child sex offenders. In the early days they were invariably Catholic offender priests, but some Anglicans as well.

Some writers identified themselves as Catholics or Catholic school teachers. Some apologised for remaining nameless to protect their jobs or families.

The message to me was "Here, I am handing this over to you, a journalist", presumably on the basis that my job is to care about matters in the public interest.

Very often these letters were not helpful at all. Saying the local Catholic church had problems with child sexual abuse, and not much else, didn't give me much to go on. I saw those letters as missed opportunities. Someone knew enough about alleged crimes against children to reach out, but these letter-writers irritated me over time.

Handing responsibility to a journalist with a next-to-useless anonymous letter is an easy way to salve your conscience, without actually becoming involved. You can "Tut-tut" with the rest about the latest excesses of the "sensationalist press" while retaining your secret inner glow.

This week federal police raided the home of a News Corp journalist and the ABC's Sydney headquarters with search warrants to access and seize documents. They related to articles in 2017 about government surveillance plans in Australia and allegations special forces troops unlawfully shot unarmed men and children in Afghanistan.

News Corp and the ABC published the articles in the public interest, believing the public has a right to know what its government agencies are doing at home, and what defence personnel are alleged to have done overseas.

Prime Minister Scott Morrison - a leader whose newly-elected government has made protecting religious freedoms a priority - was true to form in sending mixed messages about press freedoms.

His government was "absolutely committed to freedom of the press" but "no one is above the law", he said, without elaborating who, or what, exactly, is potentially "above the law" in these cases.

It was a useful motherhood statement, though. The public would hear it and agree because it's a commendable ideal. But it doesn't go that step further. Who, or what, holds governments, its elected representatives, public bureaucracies, government-owned corporations and agencies accountable, so that they're not "above the law"? You don't have to look far to find it's the media, often lined up against not only offending institutions but governments themselves. And you don't have to look far beyond that to find individuals who see wrongs, even crimes, within their organisations, institutions, bureaucracies, businesses or governments, and reach out to the media to hold people to account.

This is about power, and the exercise of power. This week's raids send a message to journalists and media outlets, but much more significantly they send a message to anyone aware of wrongs or crimes occurring, particularly within governments. The message to those individuals is look the other way, keep your mouth shut, look after yourself, it's not your problem, it's not your responsibility. And we're all cool with that, aren't we?

Back to my anonymous letter-writer.

He or she is not alleging crimes, but Catholic Church financial arrangements that would tend to disadvantage school fee-paying parents. The Royal Commission into Institutional Responses to Child Sexual Abuse recommended significant changes to Australian Catholic Church governance and structures that would open the church up to greater lay involvement and, presumably, public scrutiny of its finances.

The recommendations would tend to redistribute power within the Catholic Church so very few don't feel they're "above the law", because we know where that ends.

In 2017 John Lloyd, co-founder of the Reuters Institute for the Study of Journalism at Oxford University, wrote the book, The Power and the Story: The Global Battle for News and Information, which showed why the power of investigative journalism matters now more than ever.

After this week, read it and shudder.