Dist. Ct. erred in admitting evidence of plaintiff’s arrest record in section 1983 action alleging that defendants-police officials violated his 4th Amendment rights by stopping his vehicle for no apparent reason and threatening him at gunpoint. While jury eventually found in defendants’ favor after defendants claimed that plaintiff’s allegations were untrue, admission of plaintiff’s arrest record constituted reversible error, where: (1) such evidence is generally inadmissible due to its tendency to inflame jury; and (2) contrary to Dist. Ct.’s belief, such evidence was inadmissible for impeachment purposes where plaintiff made no factual claims regarding said arrests and was irrelevant as to whether plaintiff was law-abiding citizen. Dist. Ct. also erred in: (1) admitting evidence that plaintiff had filed two prior lawsuits against City of Chicago since such evidence was admitted only to establish litigious nature of plaintiff; and (2) admitting background testimony from police officer as to circumstances that would prompt him to pull gun on member of public, where such testimony was speculative and was contradictory to stipulated facts.