Let me begin by saying that I have never been a Nirvana fan. The sound popularized (but not created) by the Seattle bands never really appealed to me. On the other hand, I'm similarly no Hole/Courtney Love fan and I love a good conspiracy theory. That being said, I don't think this is a very good conspiracy theory based on the evidence presented above. Alias Mother Jonez does not claim to either totally believe or totally disbelieve this idea, but I know people who will go to their graves swearing by these (and other) supposed proofs for the "fact" that Kurt Cobain was murdered. This response is for them.
Kurt was divorcing Courtney
I have no way of knowing whether or not this is really the case. If it is, however, I think an argument could be made that marital problems could have provided as much of an incentive for suicide as for murder, if not moreso. According to a study undertaken by the World Health Organization in 13 European countries, "divorce was the only factor linked with suicide in every one of the 13 countries." (1) Now, obviously, it's not as if the W.H.O. was in a position to interview those who killed themselves, so I will admit that this statistic is flawed in the sense that nobody can be 100% certain of what went through these folks' minds in the moments before they ended their own lives, but it's not as if they have any compelling reasons to lie in their suicide notes or other final communications. Generally speaking, Kurt Cobain was not a happy person and these marital problems could not have helped that any. The director of the film Kurt and Courtney opined that he believes Cobain's suicide was precipitated by Love's cold behavior towards him in reference to their relationship issues. (2) It doesn't make her sound very good or do much to enhance her reputation, but that doesn't make it murder.
Someone was using Kurt's card after his death
My guess is that Courtney Love was using a credit card of his that she had previously borrowed. It's not like married people don't share finances, and given that he was the one in a really successful band (and hence the one with more money) it doesn't seem like a truly astounding leap of logic to say that she was trying to use it to buy things before she knew he was dead.
"Oh? So why would he care if the cops would come for it, if he was only going to use it to kill himself?" Most people who purchase guns do not do so for the purpose of killing themselves. In all likelihood, he really did buy it for protection and the fact that he later went on to kill himself with it is irrelevant. Even assuming that he did want it so that he could commit suicide, do you think his best friend would have helped him buy it if he had said "hey man, I need you to get me a gun so I can kill myself"? I know I wouldn't have if my friend said that to me.
The shotgun was loaded with three shells
See above. It's not a crime to preload your guns, although I wouldn't recommend it in most instances. If he kept it loaded for the purposes of self-protection, it's not really reasonable to expect him to take the other two shells out before killing himself. There's nothing that says he couldn't have changed his mind later on.
There were no fingerprints on the gun: "No fingerprints were ever found on the gun--so what did he do, blow his head off and then clean off the gun? Not likely. The gun was not tested by the Seattle Police Department for fingerprints until May 6th, almost a full month after he was found. It was then subsequently returned to Love, who had it destroyed."
First, what reason did the police have to check for fingerprints? Given the evidence readily available, they had no reason to assume it wasn't a suicide at the time. Perhaps it's not the most advisable investigation technique, but that's a problem with the police, not with Courtney Love.
Beyond that, fingerprints won't stay on a surface for all eternity. The duration of time for which a fingerprint will remain on a surface depends on (a) what created the print, (b) what surface the print was on, and (c) what the environmental factors surrounding the surface were. (3) Rub your forehead with the fingers on your right hand and then go touch your mirror with your fingertips. Now wash the fingers on your left hand, dry them, and wait about five minutes without touching or handling anything. Now touch the area next to the place where your right-hand fingerprints are with your left hand fingertips. See the difference? For the sake of your personal hygiene, I hope so. Fingerprints are left on surfaces because of naturally-secreted liquids in the human body. This can include sweat or secretions from the sebaceous glands or any number of things. (4) Looking back at your mirror, which of the two sets of prints do you suppose will clean off easier? If you guessed the left hand prints, you're correct. The different chemical compositions of the different bodily fluids have differing degrees of water solubility (among other things) and since we have no idea what Cobain was doing before he killed himself, we don't know what fluids were on his fingers when he killed himself. Because we don't know what fluids were on his fingers, we can't make a judgment as to how his fingerprints would have shown up on the surface of the gun and what it would have taken to get the prints off. That said, we don't know what conditions surrounded the custody of the weapon for the month between it was used and when it was examined. Any number of things might have caused the prints to disappear or be smudged in such a manner that they were not useable for the purposes of the examination.
As for the fact that Courtney Love had the gun destroyed, let me ask you something: if your spouse shot him or herself, would you keep the gun around for sentimental reasons? I wouldn't have.
He had already overdosed on heroin
No, he hadn't. This claim is based on a misrepresentation of the facts surrounding heroin use on the "Kurt Was Murdered" site referenced in AMJ's writeup above. To begin with, the claim that 75 mg is the lethal dosage of heroin is wrong. How did I derive this number? The amount found in Cobain's blood was 225 mg, which is said to be 3 times the lethal dosage. So, 225 divided by 3 is 75.
It is worth pointing out here that there is no such thing as a heroin blood level. Heroin is metabolized into morphine after ingestion, so the number being thrown around by the Kurt Was Murdered site refers to that. Heroin is not the only substance that is metabolized into morphine...pain killers such as codeine and even some cold/cough medications are as well. But for the sake of argument, let's ignore that and return to the 225 mg number, which is what Cobain is said to have ingested. Even this assumption is rather flawed, given that there is no way to be absolutely certain of the correlation between the amount of the actual dose and the morphine that is found in the body based on the type of test conducted by the coroner in this instance. Still, the Kurt Was Murdered site claims that Cobain ingested between 225 mg and 240 mg of heroin that day and that it should have killed him, no matter what. Let's grant the 240 mg number. A study conducted in the 1970s reveals that some heroin addicts were able to survive "doses as high as 1800 mg without even being sick" (emphasis mine). (5) This is more than 7 times the dosage purported to have been taken by Cobain and nearly 25 times the fabeled 75 mg. Where this 75 mg number came from, I have no idea, but there is scientific data to support the fact that one can (and that many routinely do), in fact, survive such a dose.
But you know what? Let's agree that Cobain had already died from a heroin overdose and someone shot him post-mortem. What is the implication being made here? That Courtney Love had someone give her husband a fatal dose of heroin while he was asleep and then shoot him to cover it up? Wouldn't he have noticed? Or did she send someone there for the purpose of giving him a fix and then have that person intentionally give him too much so he'd die? If that were the case, why not just claim he overdosed on heroin? That's much easier than some elaborate staged suicide, and they're not as easy to fake as you might believe. Really, what is gained by shooting a man who's already dead? And still, if Cobain did it to himself -- either intentionally or unintentionally --, then how does it qualify as "murder" for someone to shoot his body? You can't kill someone who's already dead!
There was no sucide note
That's a matter of opinion. There was a note of some sort and the individual interpretations one can have of it are endless. The hand-writing is a non-issue since graphology is not and has never been an exact science.
The second note
The woman is under no obligation to tell the world her personal affairs, and frankly I think we'd all be better off if she could learn to exist in such a manner that her contact with the outside world would be brought to a very, very minimal level.
He didn't leave his license out for identification
A bit of a non sequitur, wouldn't you say? I don't see this being a prerequisite for an authentic gunshot suicide. It's not like anyone else would be dead at his house while dressed in his clothes.
Really, what I'd like to say is this: Kurt Cobain was many things to many people. As I mentioned earlier, I'm not one of his fans. But you know, his most important role was not that of a tortured artist, an influential musician, a drug addict, a Mike Watt disciple, an unlikely sociological phenomenon, or even a supposed murder victim. The man was a father first and foremost. Read his suicide note. The love and the devotion he had for his daughter would be so admirable if the whole situation wasn't just so fucking tragic. This girl will suffer not just because her father chose to end his life, but because her mother seems to be dead set on destroying her own and because outsiders won't stay out of it all. Let the man rest and allow these people to get on with their existences at last.