In a cautionary tale from the Tenth Circuit this week, the Court held that a defendant forfeited any confrontation-clause challenge to limits on his cross-examination of a government witness because he failed to preserve the issue properly for appeal.
How should such a challenge be preserved? The Tenth Circuit offers clear advice:
First, make a proper proffer by describing the evidence with specificity and what it tends to show.
Second, make a proper objection by identifying the grounds for admitting the evidence. If there are multiple grounds (statutory and constitutional, say), identify them all. Invoking an evidentiary rule won't work to preserve a constitutional claim (or vice versa).
Third, explicitly link the two (the evidence with the grounds for admission).
Sounds simple, right?