Basal subarachnoid haemorrhages (BSAHs) could be traumatic and non-traumatic. The main cause for traumatic BSAH is rupture of arterial wall whilst theprimary reason for non-traumatic BSAH is the inherentand/ oracquired pathological changes of arterial wall. The current classifications do not meet the requirements of simultaneous accounting of morphological and etiological signs of BSAHs. The difficulties arising within etiological interpretation of BSAH in clinical and forensic practices are discussed.