His admission to the Leveson Inquiry today raised many eyebrows when he said: "Most of the people I deal with would be regarded as unreliable witnesses. I've had front page splashes from crack addicts.
“We do use unreliable people all the time but it's information that is important, that we vet and check thoroughly.”
As well as crack addicts, you can add to that list porn merchants, robbers, muggers, petty thieves, protection racketeers and even paedophiles.
These are the unwholesome types we must deal with every day and are listed in the contacts book of every undercover journalist worth his or her salt - tabloid or broadsheet.
They are not the sort of people you want around your dinner table. But if one says, “I know a teacher who is selling drugs to his pupils and I’ll introduce you to him”, he becomes interesting.
And once you have evaluated and proved the tip and it’s in the newspaper, he becomes invaluable.
Undercover journalists exposing crime don’t get their stories from school librarians or nursery nurses. They get them from hard boiled crooks with scores to settle.
Focusing on one crazy act of folly when he was a junior reporter nearly a quarter of a century ago makes his media detractors look small.
It's time we considered this ‘conviction’ to be well and truly spent.
To his credit, Maz has managed to escape the horrendous fall-out from the phone hacking scandal and has taken his formidable skills to the Sunday Times.
How many of his detractors in the media could claim to have won the Reporter of the Year award twice and Scoop of the Year at the British Press Awards?
Maybe they are talking to the wrong people.