Although I suspect it is unusual and although it depends on high levels of THC in the product, marijuana can kill a dog if the dog falls into a coma and suffocates on their own vomit.
There has been a 448% increase in pets ingesting marijuana in the USA causing health problems at least temporarily.
I don’t take marijuana. I don’t believe in it. But I do know that there are lots of products, human foods, in households containing THC. We know how enthusiastically dogs gobble up human food at any available opportunity. The opportunity for a dog to assume THC is quite high especially in some American states were cannabis has been legalised.