28 U.S.C. § 2254(d). If, however, the petitioner’s federal constitutional claim was raised in the state courts but remained unresolved, we apply a de novo standard. Lynch v. Ficco, 438 F.3d 35, 44 (1st Cir.2006). Under this standard, Williams’ petition should be granted if he can demonstrate that the erroneously admitted evidence so infused the proceeding with inflammatory prejudice that it rendered a fair trial impossible. Petrillo v. O’Neill, 428 F.3d 41, 44 n. 2 (1st Cir.2005). The Commonwealth contends that Williams’ federal claim was effectively adjudicated by the state court because the Massachusetts Appeals Court applied prejudicial error analysis, a standard that was at least as favorable to Williams as the federal standard. McCambridge v. Hall, 303 F.3d 24, 35 (1st Cir.2002) (<HOLDING>). The Appeals Court found that admission of the
holding that if a state case explicitly states that the state standard is more favorable to the defendant than the federal standard the federal claim is considered adjudicated below when the state standard is applied holding that the standard for withholding of removal is more demanding than the standard for asylum holding that even if the standard for waiver is clear the standard was not met holding that the standard of proof for dischargeability actions is the preponderance of the evidence standard recognizing that the federal pleading standard is a less stringent standard than the delaware pleading standard