Complex sentence: The accuracy or credibility of affidavits lack the transparency that cross-examination exacts, but--at least in civil cases--a party may be cross-examined or give an explanation or denial of its admission.
Split into simpler sentences: The accuracy or credibility of affidavits lack the transparency that cross-examination exacts. However--at least in civil cases--a party may be cross-examined or give an explanation or denial of its admission.