I ask the question in the title of this post in light of the possibility that David Kelly was murdered.
If, hypothetically, David Kelly committed suicide and no second party was present at the assumed suicide scene at Harrowdown Hill then any blood at the scene has to come from the incisions on the left wrist (if one assumes that nobody interfered with the scene).
However, if one postulates murder the number of possible sources for blood observed at the scene becomes, at least theoretically, greater:
1. Some animal blood could be smeared and/or sprayed around. DNA and other testing could readily demonstrate that such blood didn't belong to David Kelly.
2. Some human blood (but not David Kelly's) could be smeared and/or sprayed around. Again DNA and, possibly, other testing could readily demonstrate that such blood didn't belong to David Kelly.
3. The blood was from the wrist wounds, as per the "suicide hypothesis". All would check out "correctly" on DNA and other testing.
4. The blood could have been David Kelly's but not necessarily from the wrist wounds. The only credible possibility that I can think of to explain that scenario would be if David Kelly were a blood donor.
Hence the question in the title of the post.
Was David Kelly a blood donor?
I'm not saying that the "murder hypothesis" depends on David Kelly having been a blood donor. I'm simply pointing out that if David Kelly were a blood donor then an additional possible source of blood at the scene may come into consideration.