Research on ethical decision-making debates whether honesty is intuitive or controlled. Recent studies propose internalized strategies, suggesting individual propensity differences in honest or dishonest responses. This study examined how discrepancy levels of conflict affect RTs in ethical decisions for people with different internalized strategies. All the 128 participants (honest, occasional cheaters, or frequent cheaters) completed visual perception tasks (seven discrepancy levels) measuring unethical behavior. Occasional cheaters showed significantly different RTs under conflict conditions (F (6, 288) = 6.96, p < 0.001), with highest discrepancy causing longer times (mean differences from 36.84 to 47.82 ms, p < 0.01 or p < 0.001). Honest participants and frequent cheaters showed no significant differences across discrepancy levels of conflict. For frequent cheaters, there was a significant negative correlation between mean RTs difference (conflict minus non-conflict condition) and cheating frequency (r = −0.77, p < 0.001), while occasional cheaters showed a significant positive correlation (r = 0.60, p < 0.001). The study shows ethical conflict affects decision-making differently based on individuals' internalized strategies. These findings provide a nuanced view of ethical decision-making, challenging simple models and suggesting personalized approaches to promote ethical behavior.