Legalise Cannabis House curator Abe Gray arrived at the museum on Saturday afternoon to discover shards of glass in the front room of the David St museum.
An intact bottle of soft drink was found on the floor, and ''isn't the sort of thing a drunk person would be carrying in their hands'', he said.
''It seems like more than a spur of the moment type act.''
Previously he had found two smashed beer bottles near the window.
''We've been here for two years with no type of vigilante action or vandalism and I guess we picked the neighbourhood just right, and people realise we are positively contributing and they accept us.''
It was hoped the window would be replaced today.
Mr Gray said he was disappointed after contacting police to receive an email saying Dunedin police would not be pursing the incident further.
''It is obviously an act of vandalism, and the weapon, for lack of a better word is still there and probably has prints on it.''
''If it was a nana in the same neighbourhood you would hope police would (come).''
The vandalism was disappointing given the museum had been cleaned up in preparation for the Cricket World Cup, with a special cricketing exhibit set to feature for visiting fans.
