A computer expert giving evidence on what time he thinks the Bain family computer was turned on on the morning of June 20, 1994, has told the David Bain murder retrial that his findings involved a lot of “guesswork”. Police national manager for the electronic crime laboratory, Maarten Kleintjes, explained to the High Court at Christchurch the variables in the times he used to make his assessment. In 1997 he cloned the Bain computer hard drive. The technology was not available for previous witness Martin Cox to do this in 1994, to preserve the original data. He said the hardware clock in the computer was not working as the battery was flat…