You're Allowed to Question a Witness About the Fact that He's a Liar

In the case of the United States versus Jorge Cedeno, the trial judge prevented Cedeno’s lawyer from questioning a detective about the fact that he had lied (and been caught lying) in a prior court proceeding in an unrelated case. 

The trial judge prevented such questioning after considering:

1.    Whether the prior judicial finding addressed the detective’s honesty in that specific case or generally; and

2.    Whether the two sets of testimony involved a similar subject.

The court of appeals disagreed with the trial judge, however, concluding that he should have also considered such things as:

• Whether the lie was under oath in a judicial proceeding or was made in a less formal setting;

• Whether the lie was about a matter that was important or trivial; 

• How much time had gone by since the lie was told;

• Whether there had been any intervening credibility determination regarding the witness;

• The apparent motive for the lie and whether a similar motive existed in the current proceeding; and

• Whether the witness offered an explanation for the lie and, if so, whether his explanation was plausible.