I hope this message finds you well, present circumstances excluded. I am a licensed attorney with over a decade of practice experience. It is a pleasure to assist you today, though I wish under different circumstances.
The medical examiner is correct here in that for you to receive a copy of the autopsy report, you will have to get a court order. The only person that technically has access to the report, unless it is deemed a criminal matter, would be the representative of the decedent (or person that is deceased).
MN Law states, "representative of the decedent" or "representative" means the person or persons with the right to control and duty of disposition of the body of the decedent. I would assume, based on what you have shared with me, that the son was the representative of the decedent.
You can file a petition in your sister's county of residence to have a copy released to you. I believe since you are next of kin, you have a compelling reason to know the reason for her death. I think, therefore, you have a good shot a having the court order the release.
Let me know if you have any other questions or comments.
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