Nose bleeding after death does not by itself prove the cause of death.

It can happen from:

A forensic doctor must examine the body and circumstances to determine whether it reflects an injury before death, a natural process after death, or another cause. Postmortem changes can produce bloody fluid from the nostrils, so this finding alone should not be interpreted as homicide or a specific disease, as described in a review of postmortem changes.

If the death is unexpected, suspicious, involves trauma, or has not been medically confirmed, contact emergency services/police or the local coroner. Avoid washing the face, inserting anything into the nose, or unnecessarily moving the body, since this can affect assessment.

No. Bleeding from the nose after death alone does not prove brain hemorrhage.

After death, blood-stained fluid can come from the nose because of:

A brain hemorrhage can cause death, but it cannot be diagnosed from nasal bleeding alone. It requires medical assessment, typically examination of the head and brain at autopsy, and sometimes CT imaging or review of circumstances.

If there was a fall, head injury, severe headache before collapse, vomiting, seizures, unconsciousness, or blood/clear fluid from ears or nose, tell the doctor/police/forensic examiner immediately and avoid moving or cleaning the body if this is an unexplained death.