Indigenous custom as law in the Indies
A law of 1555, printed as libro II título I ley iiij of the Recopilación, orders that the laws and good customs the Indians had anciently for their government be kept and executed — while conditioning them on Christianity and on the crown's own code, and reserving the right to add. Título XV binds the Audiencias to decide Indian suits summarily "guardando sus usos y costumbres, no siendo claramente injustos", leaving to Spanish judges which customs were clearly unjust.
Why this wins its question: The usual English handling of this subject is a generalisation — Spanish law "tolerated" indigenous custom — with no statute quoted, or a flat denial that any such recognition existed. Both are cheap because the text is short and specific: a law of 6 August 1555 that approves and confirms the Indians' own laws and customs, a 1530 rule making Castile the default only where the Indies code is silent, an Audiencia ordinance requiring summary decision "guardando sus usos y costumbres, no siendo claramente injustos", set hearing days, a cost rule, and an appeal-proof clause for laws in the Indians' favour. Each is quoted here with the monarch, place and date printed in the margin of a digitised 1791 impression, and each condition and escape clause is quoted with it.
Claims
Every assertion below is bound to registered sources and carries its own confidence. Weight them; do not treat the page as uniformly authoritative.
The recognition is a statute, not an inference. Recopilación libro II, título I, ley iiij — margin "El Emperador D. Cárlos y la Princesa Doña Juana Gobernadora en Valladolid á 6 de Agosto de 1555", rubric "Que se guarden las leyes que los Indios tenian antiguamente para su gobierno, y las que se hicieren de nuevo" — orders "que las leyes y buenas costumbres, que antiguamente tenian los Indios para su buen gobierno y policía, y sus usos y costumbres observadas y guardadas despues que son Christianos … y las que han hecho y ordenado de nuevo se guarden y executen", and adds "y siendo necesario, por la presente las aprobamos y confirmamos".
The conditions are in the same sentence as the grant, and they are what makes the law a limited recognition rather than a guarantee. The customs hold only so far as they "no se encuentran con nuestra Sagrada Religion, ni con las leyes de este libro"; the crown reserves "que Nos podamos añadir lo que fuéremos servido, y nos pareciere que conviene al servicio de Dios nuestro Señor, y al nuestro"; and the closing clause protects the indigenous side only in the same conditional terms, "no perjudicando á lo que tienen hecho, ni á las buenas y justas costumbres y estatutos suyos". Who decides which customs are good and just is not said, and by the structure of the code it is the crown and its judges.
That recognition sits inside a stated hierarchy of sources printed two laws earlier. Ley ij of the same título — Charles V and the Empress in the Ordenanzas de Audiencias of 1530, Philip II in Ordenanza 312 — provides that in all cases and suits not decided by the laws of the Recopilación or by cédulas, provisiones and ordenanzas given for the Indies, "se guarden las leyes de nuestro Reyno de Castilla, conforme á la de Toro, así en quanto á la substancia, resolucion y decision de los casos, negocios y pleytos, como á la forma y órden de substanciar". Indigenous custom operated as a recognised layer within a code whose default was Castile.
The Audiencias were bound to apply custom, and this is the operative rule rather than a declaration of principle. Libro II, título XV, ley lxxxiij — margins citing Charles V's ley 20 of 1542, the Reina de Bohemia at Valladolid on 11 March 1550, Philip II's Ordenanza 70 de Audiencias of 1563, Madrid 3 July 1571, Ordenanza 79, and Toledo 25 May 1596 — orders that in suits between Indians or with them the courts "no dén lugar que … se hagan procesos ordinarios, ni haya dilaciones, como suele acontecer, por la malicia de algunos Abogados y Procuradores, sino que sumariamente sean determinados, guardando sus usos y costumbres, no siendo claramente injustos, y que tengan las Audiencias cuidado, que así se guarde por los otros Jueces inferiores".
The same título carries the procedural machinery that made the rule usable, and it is specific about cost and calendar rather than about sentiment. Ley lxxxj sets aside two days a week, and Saturdays when there are no suits of the poor, for "pleytos de Indios con Indios, é Indios con Españoles"; ley lxxxiiij orders the Audiencias to take great care not to send receptores to pueblos de Indios or elsewhere for light causes, only "sobre cosas de importancia, y mucha conveniencia"; and ley lxxxv requires that Indian business of little importance be dispatched by decree and not by provisión, "porque sean relevados de daños y costas todo lo mas que fuere posible".
Laws in favour of the Indians were given an unusual procedural force. Ley v of libro II título I — Charles V at Toledo, 4 December 1528, cap. 15, and 24 August 1529 — after stating that everything ordered in favour of the Indians has been gathered into the Recopilación, commands the viceroys, Audiencias, governors and other judges to keep and execute those laws "en todo y por todo, sin embargo de apelacion, ó suplicacion, so las penas en ellas contenidas … y de perdimiento de todos sus bienes para nuestra Cámara y Fisco, y suspension de sus oficios". Appeal did not suspend a law made in the Indians' favour, and the judge who failed to execute it risked his estate and his office.
The code also built a reporting duty back to the centre. Ley vj of the same título — Philip III at El Pardo, 25 November 1609 — orders that viceroys, presidents and Audiencias send to the Real Consejo de las Indias the ordenanzas, mandamientos and provisiones dispatched "á favor, beneficio, alivio, conservacion y buen tratamiento de los Indios, y en todas ocasiones, las que se despacharen en forma auténtica". Local rules made for indigenous towns were to travel to Madrid in authentic form, which is the mechanism by which colonial practice could become printed law.
What a compilation proves has to be stated with the compilation. These laws are evidence of what was ordered, gathered and reprinted as late as the fourth impression of 1791; they are not evidence of what was done, and nothing in this object should be read as saying that indigenous custom was reliably applied. Two of the texts quoted here contain their own warning: the 1555 law makes the recognition revocable at the crown's pleasure, and the Audiencia rule qualifies it with "no siendo claramente injustos" — a test whose application belonged entirely to the Spanish bench. The scholarship needed to measure compliance against these orders is not reachable from this working environment and no claim of compliance is made.