Thanks for pointing out distinctions that make it less clear cut whether murder is unforgiveable in Mormonism. There was a lot hiding behind my “virtually” unforgiveable. As further clarification mormon teachings distinguish between unforgiveable and unpardonable, but on some occassions that distinction is rhetorically obscurred. Only “denying the Holy Ghost” as you describe makes one bound to become a Son of Perdition and dooms one to the second Hell as described in D&C 76. On the other hand murder, is unforgiveable in the sense that the perpetrator will spend some time in the 1st Hell, or spirit prison, suffering for sin as per D&C 19:16-20 and then likely end up in the lowest of three heavens.

Of course the LDS church recognizes extenuating circumstances that make killing less clear cut. Murder is the “deliberate and unjustified taking of human life.” (EOM p. 970). First Presidency clearance is needed to baptize a murderer and at least one leader has come out against baptising murderers by proxy. As tough as church teaching is on murder, no revelation has stated that abortion is unforgivable. One wonders on how well the justifications for the that stance against murder seem to apply to abortion as well.

As the EoM puts it:

Murder violates the sanctity of life and cuts off the ability of its victims to “work out their destiny” (Benson, p. 355). Moreover, because “man cannot restore life,” and restoration or restitution is a necessary step for repentance, obtaining forgiveness for murder is impossible (Kimball, 1969, p. 129; D&C 42:18-19). Murder wrenches all lives connected to the victim, and ultimately the perpetrator of this crime suffers even more than the victims.

And

With respect to related offenses, the Church distinguishes abortion from murder but holds it an extremely grave action, not to be done except in extremely limited circumstances that might include incest or rape, perils to the life or health of the mother, or severe birth defects. As far as has currently been revealed, a person may repent and be forgiven for the sin of abortion.

If I wasn’t so lazy right now I would explain the case from doctrinal sources instead of a EOM’s survey of Mormon thought.

Better?