This is a cautionary tale about the importance of proofreading.

I was at the Old Bailey on a Friday afternoon in July 2001, waiting to hear the verdict in Jeffrey Archer's trial for perjury. He got four years.

I was reporting for the Metropolitan Police newspaper called The Job (great name!). We were about to go to press but had held space on the front page for this late-breaking news of a successful investigation.

I rushed back to Scotland Yard, wrote my story, read it through, filed it and went to the pub. My editor read it, sent it to press, and went to the pub.

Monday morning when I arrived at work all hell had broken loose. The chief press officer, the head of Public Affairs and my editor all had copies of the first issues of the paper, and were poring over my Jeffrey Archer story. They looked very serious.

The offending line was: "The investigation was hampered by the fact that several witnesses had lied..."

Seemed a fair enough statement, I thought, in innocence.

But it turned out that several witnesses had died.  If you remember, Monica Coghlan, the prostitute at the centre of the original scandal, died in a car crash shortly before the trial.

Died, lied; bit of a difference. It was pointed out to me that if the official Metropolitan Police newspaper accused witnesses of lying, they could potentially be sued by said witnesses.

Oh dear, I said. Sorry, I said.

We pulped all 40,000 copies of the paper. It cost £16,000. I remember the amount because it was exactly the same as my annual salary at the time.

I've annoyed colleagues ever since by being a stickler about this stuff. But without apology. It's absolutely vital. Mistakes in print are unprofessional, point to a lack of process and, often, to laziness. I learnt my lesson.

Disclaimer: any proofreading errors in any of these blog posts are the error of the system and no fault of mine. And besides, blogs are different.