Justifying the statutory exclusion of convicted felons from jury service, lawmakers and courts allege that convicted felons harbor an inherent bias, making them sympathetic to the plight of criminal defendants and skeptical of the prosecution. Prior research suggests that a felony conviction is a significant predictor of such pre-trial biases. The purpose of this research is to further explore that finding, examining the potential impact of lifetime incarceration and multiple felony convictions on pre-trial biases. To do so, we measured the pre-trial biases of 240 otherwise eligible jurors with a felony criminal history. Results reveal that while the presence of multiple felony convictions is a statistically significant predictor of a pro-defense/anti-prosecution pre-trial bias, length of incarceration is not, suggesting that criminal justice system contact (procedure), not punishment (outcome), contributes to the formation of a pro-defense/anti-prosecution pre-trial bias among convicted felons. Results support prior research demonstrating that criminal justice procedures are stronger predictors of convicted felons’ views than are punishment outcomes. These findings also expose the circularity of the inherent bias rationale, a justification for excluding convicted felons from a process that spawns the pre-trial biases allegedly warranting exclusion. In this way, the criminal justice system helps to build biased jurors.