How does one go about finding out the cause of a person's death ?

There is a chance there was a newspaper article about it. ("Local man killed by carbon monoxide from faulty heater"). You'd look in old newspapers on microfilm at the public library. The article would come out 0 - 3 days after the accident. There is a much smaller chance it will be mentioned in the obituary, if there was one, which will be 0 - 7 days after the death.

I also wanted to suggest inquiring on a coroner's report.

I have a great Uncle that was suspiciously ran over by a truck & another cousin that was found ' beaten unconscious' after he went out to investigate something (he was a police detective). The police reports were too old & thus purged. I found cover sheets for the coroner's reports on familysearch.org .

The County Archives (Ohio), where the deaths occurred, is the custodian of the coroners reports.(in my case) which sent me the reports after I submitted a written request. The articles I found in the paper were vague.

Depending on where the deaths occurred they may not release coroner's reports or only after a certain amount of time has elapsed. Contact the jurisdiction to find out retention & access laws.

Good Luck!

The death certificate might show the cause of asphyxiation and then it might not.

Also you may or may not be able to get one. Each state has its own laws about who,

when and where you can obtain vital records such as births and deaths on another.

You might also check and see if there was a police report.

The death records will only give you the cause of death. There may be more details in the Coroners report or in newspaper accounts.

Unless you find information in a newspaper article or the obituary, police reports and coroners reports are not public record. If you are a direct relative: child, parent or sibling you may be able to order a copy.

Get the death certificate. The death cert. should list cause of death i.e. cardiac arrest and so on.