In general, eye witness testimony is valid. However, if that person is not trustworth, then his/her statement may be in question. Moreover, other factors involving physical, mental abilities etc may also taken into consideration.

Congratulations on your thesis! We all like to think that we have good memories for events and that if we were to be witness to a crime or incident that we would be able to recall it. Have a look at the website below. www.psychblog.co.uk/eyewitness-testimony-can-you-really-trust-your-own-eyes-