A precise determination of the effective $B_s^0 rightarrow K^+ K^-$ lifetime can be used to constrain contributions from physics beyond the Standard Model in the $B_s^0$ meson system. Conventional approaches select $B$ meson decay products that are significantly displaced from the $B$ meson production vertex. As a consequence, $B$ mesons with low decay times are suppressed, introducing a bias to the decay time spectrum which must be corrected. This analysis uses a technique that explicitly avoids a lifetime bias by using a neural network based trigger and event selection. Using 1.0 fb$^{-1}$ of data recorded by the LHCb experiment, the effective $B_s^0 rightarrow K^+ K^-$ lifetime is measured as $1.455 pm 0.046 ; mathrm{(stat.)} pm 0.006 ; mathrm{(syst.)} , mathrm{ps}.$
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