Mass. Gen. Laws ch. 60, § 85: Taxes paid by co-tenants; lien on co-tenants' interest

Section 85. A tenant in common or joint tenant, who pays the entire tax assessed upon land held jointly or in common, shall have a lien upon the interest of each of his co-tenants, to secure the payment to him of the proportion of such tax payable by each of said co-tenants respectively, with the costs of enforcing the same; but any person whose tax has been so paid by his co-tenant shall have the same right to recover it back if illegally assessed as he would have had if the tax had been paid under a protest by him in writing.