After the discovery of the Higgs boson, the ultimate test of the electroweak symmetry breaking and the Standard Model (SM) of particle physics is to establish evidence of Higgs boson self-coupling, which can be achieved by searching for pair production of Higgs bosons. In addition, many theories beyond the SM predict heavy resonances that could decay into pairs of Higgs bosons. A search for non-resonant and resonant pair production of Higgs bosons in the final state with two bottom quarks and two $ tau$ leptons ($b bar{b} tau^+ tau^-$) is presented for 36.1 fb$^{-1}$ of proton-proton collis...