The detection of gravitational waves by Advanced LIGO enables us to study black hole mergers and provides a testing ground for models of gravity. We follow the constraint test used for the analysis of the double pulsar (Kramer et al 2006) and proposed for gravitational wave signals by Arun et al (2006) in which the post-Newtonian coefficients of the signal are measured and used to infer the component masses of the binary. If the model is consistent with the observation, the inferred masses from each constraint will agree. We present consistency results against general relativity spinning and non-spinning waveform templates for the binary black hole merger GW150914 and the candidate event LVT151012.