Bottom line: Sex is only a crime if there's no consent, and politicians are not built differently. Why should we expect they are?
It used to be such private matters were let lie, so they did not impact on the position; and while that might seem hypocritical, if everyone's dirty laundry was aired in public we'd be hard-pressed to find enough bums to warm the seats in Parliament.
To give one example: Rob Muldoon. His "known" vice was liquor, and he famously paid the price of letting his alcohol-impaired judgment call a snap election, thereby ensuring his downfall. But did the public know he kept a mistress, for more than a decade, in a Wellington flat close to his office? No. And neither should they have.
But other politicians knew, and police and civil servants, and the press knew too. Yet as much as Rob was detested in many circles, word of that arrangement never impinged on his political career.
Now-former Minister John Banks is an entirely different case. His mistress is money, which many consider no bad thing - even if he mistreats it. However, falsifying the detail of his election returns - as he is accused of doing - is a crime.
Notably those anomalous returns were for his mayoral campaign last time around, against Brown.
If the case is proven, Banks must resign altogether, and while John Key may play down the implications as merely a "support party" matter, the upshot would be a crisis of government, for Banks' vote is crucial. Fortunately for Key the trial date is election-time next year, so he can choose to ignore it.
Of course Banks should never have been ushered in over a cup of tea in the first place, and given the odium surrounding him since, should do the decent thing and quit now. But he won't; Banks is more die-in-the-ditch than the staunchest unionist.
Which brings up what's really odd in comparing these two cases: The public reaction to them.
On the one hand, a left-leaning centrist soundly backed for doing a good job is pilloried for a private error; on the other, a far-right walking disaster is effectively extended sympathy for an alleged criminal act.
See, mainstream media was instantly full of calls for Brown's resignation for bonking someone not his wife, but in contrast the voices suggesting Banks should quit in light of a prima facie fraud case against him are few and muted.
Fascinating, isn't it? Makes me wonder exactly where our moral compasses are trending, if celebrity fraud is seen as less important than celebrity sex.
That's the right of it.
Bruce Bisset is a freelance writer and poet.