“No. That was merely an instance of the nasty suspicious turn a detective’s mind instinctively takes. I didn’t know that there had been any quarrel. But I did assume for the time that you had murdered Miss Palfreeman, and if you had done so, then surely it was only logical to make the assumption of a quarrel too?”
“You did really suspect me then, and leave me at large? Surely that was a risk to take?”
“No, as you will see later I did not altogether suspect you. But I did when I was questioning you at my inquiry. When you treat a patient, Doctor, you diagnose the disease and then you treat him for it, and you work consistently on the assumption that your diagnosis has been correct until you find out definitely that you have made a mistake. You don’t make up your medicines to suit two or three possible ailments on the off chance that one of them may be correct. Well, my own experience has taught me that at an inquiry like the one we had round the dining-room table on the Wednesday morning, the only possible way to obtain exact information is to assume that the questionee is guilty. It is no good making up your mind beforehand that X is guilty and allowing that to color all the questions you put to Y. I believe that my success as a detective is due to the fact that for a time I can force myself into believing what I don’t really believe, more than to anything else. I questioned each of you as Miss Palfreeman’s murderer. As I questioned you I was convinced of your guilt. Then, when it was over, I was able to stop play-acting, and sift out the information I had secured.”
The conceited little fellow looked round brightly for approbation after the manner of some small boy who knows he’s said something rather smart. Self-satisfied little beggar! Just when I was beginning rather to like him too! The Tundish murmured something about a doctor’s diagnosis not always being quite the pig-headed business he’d described, and Allport, filling up his pipe again, continued.
“As I was explaining, it was inevitable that my first suspicions should turn to the doctor, but there were several points that led me to think it might be a mistake to make an immediate arrest without further investigation. On the floor, near the bedside table, in Miss Palfreeman’s room, I had picked up a tiny fragment of splintered glass and a good-sized diamond.
“The diamond had evidently fallen out of the setting on a ring or a broach—it might have belonged to any one—most likely to Miss Palfreeman herself, but when we came to search the bedrooms we found no piece of jewelry from which a stone was missing. It struck me as being rather strange that its loss had not been advertised. Annie had heard nothing of it and none of you had questioned her about its loss. It was possible, of course, that the owner might not have noticed that it was missing, but then I should have expected to find a damaged ring either among Miss Palfreeman’s belongings or in one of the other bedrooms. Not very much to go on, perhaps, but I felt it to be unnatural that a diamond of such considerable value should be lost and nothing said.”
It was my turn to interrupt, and unlike his previous attitude, the little man seemed now almost to welcome the interruption. I could see that he was in the throes of an exquisite—and I must admit a thoroughly deserved—enjoyment. He was like a child, I thought, sucking its favorite sweet, and making it last. I told him how I had caught Margaret searching the stairs for a sixpence that Annie found for her later on, and how my half-awakened suspicions had been allayed by the find.
Then The Tundish informed us that he too had seen her searching, but in his case on the floor of poor Stella’s room. He had been mounting the stairs to the upper landing. The door of the room was half closed, and he had seen movements within, or had fancied that he had. But when he had pushed the door open to see what it was, he had found Margaret kneeling devoutly in prayer at the side of the bed.
Once again I was amazed at the placid doctor’s powers of description. He was uncanny. He described the little incident in the fewest possible simple words, but like the bold strokes of a master they made the picture live. Margaret, on hands and knees, half frantic, searching the floor for her incriminating diamond—then a sudden creak on the stairs, and the doctor gently pushing open the door to find her kneeling in prayerful attitude at the side of Stella’s bed—an attitude, surely, to make angels weep and Sapphira jealous.
The little man smoked thoughtfully for a few minutes, rearranged the cushions at the back of his chair, and continued.