Iceland chairman Malcolm Walker has given evidence at the trial of 28 Greenpeace supporters charged with theft and criminal damage after they destroyed a trial crop of genetically modified maize at a Norfolk farm. Walker, who has been a member of Greenpeace for 10 years, said the defendants had a lawful excuse to destroy the GM crops which they genuinely believed could contaminate neighbouring organic crops. Walker told the court: "It is almost biologically impossible for something to be GM free because of cross contamination or cross pollination. The public do not want contamination of any degree." He said Iceland was careful not to mislead customers by labelling products GM free' when this might not be the case due to contamination. {{NEWS }}