[Tenant, US-MD] Repair payment question

So I am currently renting a room in a house and have several other roommates, the landlord also lives here. Recently someone broke a shot glass in the sink and the garbage disposal became clogged and would not run and the sink would not drain (we are not sure if it is the result of the shotglass or another reason and we are not sure who is responsible for the damage). The landlord is trying to make us tenants split the cost of repairs. However we feel it is the landlord's responsibility. We have also never been given copies of our lease. I was just wondering what we should do in this situation.