English law has no official means of correcting a "perverse" verdict (conviction of a defendant on the basis of insufficient evidence). Appeals are based exclusively on new evidence or errors by the judge or prosecution (but not the defence), or jury irregularities. A reversal occurred, however, in the 1930s when William Herbert Wallace was exonerated of the murder of his wife. There is no right to a trial "without" jury (except during the troubles in Northern Ireland or in the case where there is a significant risk of jury-tampering, such as organised crime cases, when a judge or judges presided without a jury).