HAMILTON - The trial of a man accused of murder through the transmission of HIV is hearing officials had `tunnel vision' in not checking other men as the source of the virus.

Johnson Aziga, 52, has pleaded not guilty to two counts of first-degree murder and 11 counts of aggravated sexual assault.

The Crown alleges the HIV-positive man engaged in unprotected sex without telling his partners he carried the virus.

Aziga's lawyer, Davies Bagambiire, is telling a Hamilton court at least one other man with the same rare HIV- subtype had sex with some of the women Aziga is accused of infecting.

Bagambiire questions the scientific value of the Crown's expert evidence, saying their sampling overlooked local men.

He also spoke of Aziga's mental state, saying he suffers from mental disorders, including post-traumatic stress disorder, which can lead to bad judgment.