A soil expert has told how she helped catch the killer of Irish student Karen Buckley – because dirt on his car had been missed when he had it cleaned.
Alexander Pacteau was jailed for life in 2015 for brutally murdering Karen, 24, after meeting her at a Glasgow nightclub.
The former private schoolboy, then 21, took Karen to his car where he strangled her and repeatedly hit her on the head with a foot-long wrench.
