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In general, when a party has been guilty of laches in enforcing his right by great delay and lapse of time, this circumstance will at common law pre-judice, and sometimes operate in bar of a remedy which it is discretionary and not compulsory in the court to afford. In courts of equity, also delay will generally prejudice. 1 Chit. Pr. 786, and the cases there cited; 8 Com. Dig. 684; 6 Johns. Ch. R. 360.

But laches may be excused from, ignorance of the party's rights; 2 Mer. R. 362; 2 Ball & Beat. 104; from the obscurity of the transaction; 2 Sch. & Lef. 487; by the pendency of a suit; 1 Sch. & Lef. 413; and where the party labors under a legal disability, as insanity, coverture, infancy, and the like. And no laches can be imputed to the public. 4 Mass. Rep. 522; 3 Serg. & Rawle, 291; 4 Henn. & Munf. 57; 1 Penna. R. 476. Vide 1 Supp. to Ves. Jr. 436; 2 Id. 170; Dane's Ab. Index, h. t.; 4 Bouv. Inst. n. 3911.