Does a district judge abuse his position by refusing to rule in advance as to the admissibility of prior convictions?

In this case, however, we need not decide whether the district judge abused his discretion by refusing to rule in advance as to the admissibility of prior convictions. The record is clear that Tercero did not demonstrate, as he must, that he was prejudiced by the ruling. United States v. Cook, supra at 1188 (Wallace, J., concurring). To do so, Tercero must show that he would have testified but for the court's refusal to rule in advance. Id. This he cannot do. The record plainly reveals that even if the court had ruled in advance that the prior convictions were inadmissible, Tercero would not have testified due to the existence of a potential rebuttal witness, one who had previous drug dealings with Tercero. ⁸ Consequently, Tercero cannot claim injury as a result of the court's ruling.