For Mathias Cormann, 2018 has been the annus horribilis. After emerging badly bruised from the leadership crisis, on Tuesday he took responsibility for the disastrous snafu over Pauline Hanson’s “It is OK to be white” motion.

The government blames its voting on Monday in support of the motion on an “administrative” error.

The ordinary voters might find that explanation little short of Orwellian.

Whatever the so-called “process” problems, the public might ask: what does it say about Coalition senators that they would vote mindlessly for anything they are told to back, however inappropriate?

After all, following a short but pithy debate Coalition senators sat to be counted, with the white supremacist language there before them, if they had their notice papers, and opposition and Green senators yelling to bring their attention to it.

The motion said: “That the Senate acknowledges:

(a) the deplorable rise of anti-white racism and attacks on Western civilisation; and

(b) that it is okay to be white.”

When these Senate motions – on average there are 50-60 every sitting week – come, the government asks the relevant ministerial office to advise. In this case, it was the office of Attorney-General Christian Porter.

Porter says his staff interpreted Hanson’s as “a motion opposing racism. The associations of the language were not picked up”. An email was sent - advising support - “without my knowledge”.

Porter put the blame on his staff – in fact two were involved - for misinterpreting the motion and so failing to “escalate” it up to him.

One would have thought ministerial staff would be particularly alert to Hanson motions, and think very carefully before concluding she was doing something as unlikely as putting forward an anti-racist one.

Porter’s office gave its first advice in September, when the motion was lodged.

But in a tactics meeting Cormann, who is Senate leader, overrode the view from the Porter office. The Senate leadership decided the Coalition would oppose the motion, accompanying its opposition with a statement that the government condemned all forms of racism.

The motion was expected to come to a vote on September 20 but the Senate ran out of time.

When the motion was looming this week, unbeknown to Cormann fresh advice was sought from Porter’s office, which again declared it should be supported.

Cormann was paired and not in the chamber when it was dealt with; he only found out the government had voted for it after the event (it was defeated 31-28). Cormann hadn’t been informed that his earlier decision had been overridden by the latest advice from the Porter office. Another failure of “escalation”.

Cormann threw himself under the blame bus on Tuesday, but actually he’d tried earlier to stop the government being run over by the Hanson truck.

Despite the government’s handwringing on Tuesday – which led to it having the motion recommitted in the Senate so it could vote against it – on Monday night Porter was tweeting “The Government Senators’ actions in the Senate this afternoon confirm that the Government deplores racism of any kind.”

Cormann said “The Government indeed deplores racism of any kind” in a tweet quoting Porter’s.

It was when the government started feeling the heat – which it is very sensitive to before Saturday’s Wentworth byelection – that it knew it had better do something.