A former government scientist has called into question the work of the prosecution's key expert witness in the case of the 21/7 bombers.
Sean Doyle, used to be the principal scientist at the government's Forensic Explosives Laboratory (FEL).
In a witness statement, Mr Doyle said a number of FEL scientists "openly expressed concerns" relating to the work of Dr Black.
The methodology employed by Dr Black and the interpretation of the results may not be reliable.
In my opinion, the scientific evidence presented by Dr Black was not treated with the caution required of a novel forensic technique.