There is accident then there is accident, then again there is accident.
There is an accident where the child is riding a bike, falls and strikes her head. Usually 911 will be called.
Then there is accident where the adult is backing their vehicle and strikes a child. Usually 911 will be called.... unless they feel they could be liable for some other type of crime, like DUI.
Then there is accident like the man who beats and strangles his wife for hours. But he feels it was an accident, because he didn't mean to kill her... he just wanted to hurt her bad.
Then there is the serial killer, who claims the killings were accidents because he was just trying to shut them up and keep them from screaming. He might not have been done with them yet.
IOW what the perp says about accident doesn't mean much. If it was a true accident with no involvement from the perp- why didn't she call 911? Besides when a perp starts to break in talking with police, they will usually start with "it was an accident." IOW they try to minimize their culpability. But it doesn't mean it is true, it just means that was as much as she was willing to admit to at that time.
My understanding of the degrees of culpable death. Usually manslaughter, 2nd degree or 1st degree. Manslaughter- more or less an avoidable death, in which the perp played some role but didn't have an intention of killing and perhaps to some degree other forces were involved in the death or death could not have been reasonably expected. Two people fighting in the yard and one shoves the other into the street- a car turns the corner at just that time and strikes the victim.
2nd degree- perp didn't intend to kill, but took action where death was a reasonable expection- No premeditation. Assault with a deadly weapon resulting in death, drugging a child could fit under this I think.
1st degree- premedation, too action with the intent to kill, took action where death was a reasonable expectation.
If there is a person who had involvement in the death, who was also in commission of a crime, it will be called murder. The only thing that might be different is in the degree of murder that might be charged.
Theory: If rumors are to be believed and MH had drugged Sandra before, then that shows she knew what and how much of a drug to administer, and how to make sure the child was found so that permanent injury could be avoided. If it worked before, it should have worked again, right? Well that isn't necessarily true. The drug caused unconciousness before, and Sandra was found and taken to the hospital. This time she wasn't found in time. I'm thinking that Sandra was taken at MH's home, perhaps transported to the church in the suitcase while still alive. That might have compromised her ability to breathe and caused her death- possibly on the way home.
If that happened there may not have been an intent to kill. But the death happened during the commission of another felony which should jack up the degree. Some states also have something in the law that if you cause the death of a child during the commission of a felony, that makes it death penalty eligible.
Could she have done the abuse after death to try to make it look like a man had killed Sandra? Then why redress her and try to conceal the evidence? The autopsy should have been able to detect if the abuse happened before or after the death, and possibly she may have talked about what happened during her interrogation when she found out she was being charged with rape. If it was after death that would have resulted in different charges. Previous history, rumor or MH's own words indicate she might have kidnapped Sandra and molested her before, so it is doubtful.
JMO