Malice in the Highlands by Graham Thomas

So far so good. But one would normally expect a person falling backward as a result of his feet slipping out from under him to land hard on his arse or back. And one wouldn't be at all surprised if he were to injure an elbow or a wrist while attempting to break the fall. It is in fact difficult to conceive how he could strike his head by falling, as hard as Murray was struck, without sustaining other minor scrapes and bruises in the process. Yet, according to Dr. Campbell, the contusion on the back of the head was the only visible injury occurring prior to death.”
    PC Shand listened with rapt attention.
    “The same difficulty arises when one considers the possibility of suicide. Jumping off a bridge, for instance.But if one accepts the possibility that Murray was murdered, it all begins to make sense.”
    Shand coughed politely as if he were about to say something, but he apparently thought better of it.
    “Suppose Murray accompanied someone down to the river on some pretext or other,” Powell continued. “When the opportunity arose, his assailant bashed him on the head and then chucked him into the drink, hoping that when the body eventually turned up it would look like an accident. Thus the significance of the diatom test.”
    PC Shand wore a puzzled expression.
    Powell explained patiently, “Look, if the test had been negative, suggesting that Murray had died before going into the river, we would have been left to account for some rather improbable behavior on the part of our hypothetical assailant.”
    “I'm still not sure I follow you, sir.”
    Powell sighed. “Why would anybody leave their victim lying unconscious on the riverbank to be discovered by the next passerby? The killer could not have been certain that the river would subsequently flood to conceal his crime. No, I'm afraid that we'd have been left with the unavoidable, however unsatisfying, conclusion of accidental death. So it is fortuitous, if I may put it that way, that Murray was still alive when he was pushed or dragged into the water.”
    PC Shand nodded his head doubtfully. “Yes, I think I understand now, sir.” Actually, it seemed to him that Powell's reasoning was somewhat elliptical, but he wisely chose not to pursue the point. “Maybe the act wascommitted in the heat of the moment, a crime of passion, like.”
    The constable's boyish enthusiasm was beginning to wear a bit thin. “That's possible, of course,” Powell said crisply. “Now, then, how are you getting on with your own inquiries?”
    PC Shand drew himself up and cleared his throat. “Well, sir, I've had a wee chat with MacDougall, the gillie at Cairngorm who found the body. Nothing new there, I'm afraid. The man seemed more concerned with avoiding further publicity than answering my questions.”
    Powell could well imagine. “Any news of the elusive Oliver Pickens?”
    “Not yet, sir. We've checked with British Rail at Aviemore. None of the staff on duty Monday afternoon have any recollection of anyone matching either Murray's or Pickens's description. It seems fairly certain that Pickens did not buy a ticket at Aviemore. He may have had a return ticket, or possibly a BritRail pass. In either case, he could have boarded a train without direct contact with station personnel. We're presently checking all departures from Aviemore on Monday and interviewing all employees who might have come in contact with him along the line. We're also making inquiries at the local taxi stands, coach lines, car rental agencies—you know, the usual routine, sir.”
    Powell suppressed a smile. The young constable had taken to his task like a salmon to a burn. “I don't doubt something will turn up eventually.”
    “I hope so, sir. I've still not been able to come up with anyone who saw either of them after they left Castle Glyn.”
    “Well, carry on. It's early innings yet.”
    “Very good, sir. I'd best be off then.” Shand paused a little awkwardly. “Will there be anything else, Mr.