Conservation groups have criticised the expected appearance of a top Transport Bureau official as a key witness for the KCRC in its appeal against a ban on the Lok Ma Chau spur line. Principal Assistant Secretary for Transport William Shiu Wai-chuen is a likely witness for the rail firm in its fight for permission to put the new line through the Long Valley bird haven. The appeal starts tomorrow. Plato Yip Kwong-to, of Friends of the Earth, said it 'would give the public a wrong message that the Government is defending a commercial entity'.