Bollocks. Lots of crimes go unreported. People attacked at a canalside would possibly be involved in something they didn't want to be made public (crime, homosexual liaisons), so any survivors wouldn't necessarily want to tell the tale.
This poor bloke going on his holidays http://www.irishtimes.com/news/crim...normal-man-going-about-his-business-1.2502798
Odd one,no form,seemed decent enough.They reckon got into a row and got battered and killed,chainsaw job to hide body but not very clever if body found 2 days later.
If I was the Manchester canal pusher I would handcuff the victims to shopping trolleys before pushing them in. Try swimming with a trolley Shergar .
It reminds me of a scene from the Marx Bros when Groucho opens his trunk to find Chico and Harpo inside.
If the victim managed to swim and climb out of a slippery canal one handed with a trolley then he would get a round of applause.