They can evict you for smoking it, not having it in your unit or even being in possession of paraphernalia. They have to have physical proof of you smoking inside the unit - and complaints of smell around the building is not exactly proof of one person being complacent or violating the building rules or lease. Plus, eviction takes forever and happens in a JP court, where there’s no jury, just a judge. It’s also on the burden of the landlord to provide proof of that evidence in the form of exhibits to the judge. I’ve managed so many properties… including subsidized housing where maintenance techs regularly found bongs, needles, and all sorts of other items, which in my opinion should have constituted an eviction, but that’s just not how the law works. Plus, it’s very expensive for landlords to peruse eviction. It’s not good on their rent rolls or pocket books. With that said, regular notices of a lease violation on top of other residence’s testimony/complaints might convince a judge to peruse eviction. It all depends on the judge.