Senate inquiries aren’t always torrid affairs for public servants. Indeed, most of the time they’re relatively innocuous.

It may not look it but senators are usually outmatched when grilling public servants. Opposition and minor party senators and their staff can’t cover issues in anywhere near the depth of public servants who live and breathe the issues every day. When you sit at that desk looking across at senators, you can usually be confident you know far more about what you’re about to discuss than your interlocutor. The biggest challenge is making sure you know where every dollar in a program is, because that’s where Oppositions usually focus their attack.

Moreover, as a public servant you’re not paid to help Opposition senators. If they ask the wrong question, you don’t give them the right one. You answer it. You give lengthy answers on innocuous issues so that you chew up time. You divert Opposition senators with tangential issues. And a capacity to give the impression you’re telling senators something irrelevant not widely-known is invaluable. You can chew up any amount of time that way, and there’s only a limited amount of time for such interrogations.

That’s why it takes a rare senator, like John Faulkner, with the patience and wit to actually match the public servants at their own game.

Some public servants find it nerve-wracking. Others find it great sport. The pleasure of sending the Opposition down a rabbit-hole when they thought they were closing in on something, or of besting a Senator trying to argue a point, is immense. I rarely got to sit at the table and offer my two cents worth as a bureaucrat, usually because my managers were well-briefed enough and smart enough to handle just about anything thrown at them by the Opposition with ease. Or perhaps they didn’t trust me not to stuff it up. But when I was asked to trouble the scorers at such hearings, I thought it enormous fun.

For most, though, it’s part of the job and it’s not especially enjoyable, mostly because preparation takes up enormous amounts of time better spent on doing real work.

But occasionally senators are armed with inside information, and that’s when they have the advantage. Rather than groping around in the dark, not sure what the right question is let alone the answer, they can then zero in on exactly what the Government would prefer to keep hidden. That’s when the tables are turned, and unless you’re on top of your game, you can find yourself in deep trouble very quickly, wrecking your own career and that of your minister as well.

That’s what happened on Friday. If the Charlton email was fake, the Opposition still had a lot of other material to work from, and Eric Abetz did it beautifully. He stayed polite, and focussed, and very patient, even happily yielding to Doug Cameron at one point, knowing full well he would have more time later.

Godwin Grech and David Martine handled the pressure differently. Martine, the more experienced officer, tried to obfuscate and hinder the Opposition as much as possible, and never more so than when he successfully prevented Grech from answering the question about Andrew Charlton. Contrary to Brian Toohey’s outraged exclamations on Insiders yesterday, Martine was fully within his rights as the senior officer to insist on answering the question. A Senate inquiry is not a courtroom, and senior Departmental officers are entitled to take questions, no matter how bad it looks.

And it may have looked like Treasury had something to hide but Martine was only doing what many public servants do, which is ensure the Opposition gets no free points.

Grech, a man of almost Dickensian visage and name, chose absolute honesty, an approach that, unless you’re very confident in your own evasive skills, is probably wisest, especially when it is clear that the Opposition has plenty of primary material to work with. He wasn’t badgered or harassed by his inquisitors, but he nevertheless was acutely aware that his honest recollections were going to set off a bomb under the Government, and that is enough to give any honest public servant palpitations, no matter their personal politics.

Grech would have felt the loneliest man in the world for much of Friday afternoon.