In what circumstances will a court order an evidentiary hearing to determine whether the plea was coerced?

Mayes was followed nearly a decade later in Marrow, 772 F.2d at 527, in which this court remanded the case for an evidentiary hearing to determine whether the appellant's plea was coerced by threats. Again, the court relied on the fact that the allegations involved matters outside the record of the case, and thus concluded that a hearing was required under 2255. Id. See also, Iaea v. Sunn, 800 F.2d 861, 866-68 (9th Cir.1986) ( 2254 case remanded for evidentiary hearing on allegations of plea coercion).¹