Lindsay looked up. “It was clear to Miss Overton that since you had already made an arrest that fitted the circumstances, you wouldn’t be looking for alternative solutions. So she asked Cordelia and me to take a look at this business to see if we could come up with anything that would help clear Paddy Callaghan, whom all three of us believe is innocent.

“I have been a journalist for some years now,” she went on, finding her stride. “I’ve done a fair number of investigations, a couple of which have resulted in arrests. I have qualifications both in English and Scottish law, and I know quite a bit about the burden of proof. If I didn’t, I’d be too expensive a risk for newspapers to employ. I’m not as much of a fool as you seem to think, Inspector. And neither is Cordelia. I thought we might just manage to come up with one or two things that you and your experienced team had missed, especially since people seem to find it easier to talk to us. As for messing about on the kitchen roof with the scaffolding—it was testing a theory that seemed to cover all the salient facts.”

“Spare me the speeches,” he said caustically.

She ignored him and continued. “I don’t particularly expect you to believe this, but all week I’ve had something nagging away at the back of my mind. I had a feeling it was important, but it just wouldn’t come to me. I only remembered what it was in the early hours of this morning.”

Then she explained the sudden realization of what she had seen so briefly the week before. She went on to relate the events of the morning. When she came to the end of her tale, he looked aghast.

“God preserve me from amateurs,” he said bitterly. “And just how many fingerprints, footprints, and other forensic traces do you think you obliterated this morning? What in heaven’s name possessed you to take the law into your own hands to this extent? Answer me, woman!”

“I didn’t think there would be anything on the building site. After all, the workmen have been there all week. As far as the rest of it is concerned, I supposed the criminal would have been wearing gloves. It wasn’t a spur of the moment crime, and everyone knows about fingerprints these days. And Chris Jackson made sure she didn’t do any damage to the paintwork. There weren’t any marks on it before, anyway. I checked early this morning when I realized what it was I’d seen last Saturday.”