THE CHAMIZAL CASEPARTIES: Mexico, United States of America.COMPROMIS: Convention of 24 June 1910.ARBITRATORS: International Boundary Commission: E. Lafleur;A. Mills ; F. Beltram y Puga.AWARD: 15 June 1911.Title to the Chamizal Tract — Boundary rivers — Effects of natural change inthe course of such rivers — Treaty interpretation — Retroactive effects of treatyprovisions — Prescription.1For the questions at issue, the background of this case, and for the contentionsof the Parties, see the introductory part of the award.

BIBLIOGRAPHYA. M. Stuyt, Survey of International Arbitrations 1794-1938, The Hague, 1939,p. 313Texts of the Compromis and AwardAmerican Journal of International Law, Vol. 5, 1911, Supplement, p. 117[English text of the compromis]; vol. 5, 1911, p. 787 [English text ofthe award]British and Foreign State Papers, vol. 103, p . 588 [English text of the compromis]De Martens, Nouveau Recueil général de traités, 3 e série, t. IV, p. 719 [Englishand Spanish texts of the compromis] ; 3 e série, t. VI, p. 66 [Englishtext of the award]Papers relating to the Foreign Relations of the United States, 1911, p. 566 [Englishtext of the compromis] ; p. 573 [English text of the award]Treaties, Conventions, International Acts, Protocols, and Agreements between theUnited States of America and other Powers, vol. I l l , p. 2729 [English text ofthe compromis]CommentariesAmerican Journal of International Law, vol. 4, 1910, p . 925; vol. 5, 1911, p. 709.Argument submitted by the Government of the United Mexican States to the HonorableArbitral Tribunal and the Agent of the Government of the United States of Americaunder the provisions of Article V of the Arbitration Convention for the " El ChamizalCase " dated June 24th, 1910, Mexico, 1911.Brief presented by the Government of the United States of Mexico to the Agent of theGovernment of the United States of America in accordance with Article V of theArbitration Convention in regard to the Chamizal Case, dated June the 24th, 1910.1911.Chamizal Arbitration, Arguments, Case and Countercase of the United States ofAmerica . . ., Washington, 1911 (5 volumes)Chamizal Arbitration, United States and Mexico, minutes of the meetings of theInternational Boundary Commission, June 10 and 15, 1910, containing the awardin the Chamizal Case, Washington, 1911.Demanda, Réplica, Alegato é informes presentados por el Licenciado Joaquin D.Casasus ante el Tribunal de Arbitrajey sentencia pronurwiada por el mismo tribunal,Mexico, 1911.Memoria documentada del juicio de arbitraje del Chamizal celebrado en virtud de laConvention dejunio 24 de 1910 (3 volumes), Mexico, 1911.Papers relating to the Foreign Relations of the United States, 1910, p. 716; 1911,p. 565; 1913, p. 957.Rivista di diritto intemazionale, vol. 8, 1914, p. 67.

CONVENTION FOR THE ARBITRATION OF THECASE CONCLUDED ON 24 JUNE 1910 1CHAMIZALThe United States of America and the United States of Mexico, desiring toterminate, in accordance with the various treaties and conventions now existingbetween the two countries, and in accordance with the principles of international law, the differences which have arisen between the two Governmentsas to the international title to the Chamizal tract, upon which the membersof the International Boundary Commission have failed to agree, and havingdetermined to refer these differences to the said commission, established by theconvention of 1889, which for this case only shall be enlarged as hereinafterprovided, have resolved to conclude a convention for that purpose, and haveappointed as their respective plenipotentiaries:The President of the United States of America, Philander C. Knox, Secretaryof State of the United States of America ; andThe President of the United States of Mexico, Don Francisco Leôn de laBarra, ambassador extraordinary and plenipotentiary of the United States ofMexico at Washington;Who, after having exhibited their respective full powers, and having foundthe same to be in good and due form, have agreed upon the following articles :Article I. The Chamizal tract in dispute is located at El Paso, Texas, andCiudad Juarez, Chihuahua, and is bounded westerly and southerly by themiddle of the present channel of the Rio Grande, otherwise called RioBravo del Norte, easterly by the middle of the abandoned channel of 1901, andnortherly by the middle of the channel of the river as surveyed by Emory andSalazar in 1852, and is substantially as shown on a map on a scale of 1-5,000signed by General Anson Mills, commissioner on the part of the United States,and Senor Don F. Javier Osorno, commissioner on the part of Mexico, whichaccompanies the report of the International Boundary Commission, in CaseNo. 13, entitled " Alleged Obstruction in the Mexican End of the El PasoStreet Railway Bridge and Backwaters Caused by the Great Bend in the RiverBelow ", and on file in the archives of the two Governments.Article II. The difference as to the international title of the Chamizal tractshall be again referred to the International Boundary Commission, which shallbe enlarged by the addition, for the purposes of the consideration and decisionof the aforesaid difference only, of a third commissioner, who shall presideover the deliberations of the commission. This commissioner shall be aCanadian jurist and shall be selected by the two Governments by commonaccord, or, failing such agreement, by the Government of Canada, which shallbe requested to designate him. No decision of the Commission shall be perfectly valid unless the commission shall have been fully constituted by the threemembers who compose it.Article III. The commission shall decide solely and exclusively as to whetherthe international title to the Chamizal tract is in the United States of America1Papers relating to Foreign Relations of the United States. 1911, p . 566.

314MEXICO/UNITED STATESor Mexico. The decision of the commission, whether rendered unanimouslyor by majority vote of the commissioners, shall be final and conclusive uponboth Governments, and without appeal. The decision shall be in writing andshall state the reasons upon which it is based. It shall be rendered withinthirty days after the close of the hearings.Article IV. Each Government shall be entitled to be represented before thecommission by an agent and such counsel as it may deem necessary to designate ;the agent and counsel shall be entitled to make oral argument and to examineand cross-examine witnesses and, provided that the commission so decides, tointroduce further documentary evidence.Article V.1 On or before December 1, 1910, each Government shall presentto the agent of the other party two or more printed copies of its case, togetherwith the documentary evidence upon which it relies. It shall be sufficient forthis purpose if each Government delivers the copies and documents aforesaidat the Mexican Embassy at Washington or at the American Embassy at theCity of Mexico, as the case may be, for transmission. As soon thereafter aspossible, and within ten days, each party shall deliver two printed copies ofits case and accompanying documentary evidence to each member of the commission. Delivery to the American and Mexican commissioners may be madeat their offices in El Paso, Texas; the copies intended for the Canadian commissioner may be delivered at the British Embassy at Washington or at theBritish legation at the City of Mexico.On or before February 1, 1911, each Government may present to the agentof the other a countercase, with documentary evidence, in answer to the caseand documentary evidence of the other party. The countercase shall bedelivered in the manner provided in the foregoing paragraph.The commission shall hold its first session in the city of El Paso, State ofTexas, where the offices of the International Boundary Commission are situated,on March 1, 1911, and shall proceed to the trial of the case with all convenientspeed, sitting either at El Paso, Texas, or Ciudad Juarez, Chihuahua, asconvenience may require. The commission shall act in accordance with theprocedure established in the Boundary Convention of 1889. It shall, however,be empowered to adopt such rules and regulations as it may deem convenientin the course of the case.At the first meeting of the three commissioners each party shall deliver toeach of the commissioners and to the agent of the other party, in duplicate,with such additional copies as may be required, a printed argument showingthe points relied upon in the case and countercase, and referring to the documentary evidence upon which it is based. Each party shall have the right to filesuch supplemental printed brief as it may deem requisite. Such briefs shallbe filed within ten days after the close of the hearings, unless further time begranted by the commission.Article VI. Each Government shall pay the expenses of the presentation andconduct of its case before the commission; all other expenses which by theirnature are a charge on both Governments, including the honorarium for the1In accordance with a Supplementary Protocol, signed at Washington on5 December 1910, the date for the presentation of the respective cases and documentary evidence was fixed for 15 February 1911; the date for the presentation of therespective countercases and documentary evidence was fixed for 15 April 1911;the date for the first session of the Commission was fixed for 15 May 1911. (For thisProtocol see: Papers relating to Foreign Relations of the United States, 1911, p. 569.)

CHAMIZAL CASE315Canadian commissioner, shall be borne by the two Governments in equalmoieties.Article VII. In case of the temporary or permanent unavoidable absence ofany one of the commissioners, his place will be filled by the Government concerned, except in the case of the Canadian jurist. The latter under any likecircumstances shall be replaced in accordance with the provisions of thisconvention.Article VIII. If the arbitral award provided for by this convention shall befavorable to Mexico, it shall be executed within the term of two years, whichcannot be extended, and which shall be counted from the date on which theaward is rendered. During that time the status quo shall be maintained in theChamizal tract on the terms agreed upon by both Governments.Article IX. By this convention the contracting parties declare to be null andvoid all previous propositions that have reciprocally been made for the diplomatic settlement of the Chamizal case; but each party shall be entitled to putin evidence by way of information such of this official correspondence as itdeems advisable.Article X. The present convention shall be ratified in accordance with theconstitutional forms of the contracting parties and shall take effect from thedate of the exchange of its ratifications.The ratifications shall be exchanged at Washington as soon as possible.IN WITNESS WHEREOF, the respective plenipotentiaries have signed the abovearticles, both in the English and Spanish languages, and have hereunto affixedtheir seals.DONE in duplicate at the city of Washington, this 24th day of June, onethousand nine hundred and ten.Philander C. KNOX [SEAL]F. L. DE LA BARRA [SEAL]

AWARD BY THE INTERNATIONAL BOUNDARY COMMISSIONIN THE MATTER OF THE INTERNATIONAL TITLE TO THECHAMIZAL TRACT, RENDERED ON 15 JUNE 1911 »Titre sur le territoire dit « Chamizal » — Fleuves frontières— Effets des modifications naturelles du lit de tels fleuves—Interprétation des traités—Effetsrétroactifs des traités— Prescription.PREAMBLEWHEREAS a convention between the United States of America and theUnited States of Mexico for the arbitration of the differences which havearisen between the two Governments as to the international title to the Chamizaltract was concluded and signed by their respective plenipotentiaries at Washington on the twenty-fourth day of June, 1910, which is as follows: zAND WHEREAS the said convention was duly ratified on both parts and theratifications of the two Governments were exchanged at the city of Washingtonon the twenty-fourth day of January, 1911.AND WHEREAS on the fifth day of December, 1910, the plenipotentiaries whonegotiated and signed the said convention of June 24, 1910, being thereuntoduly empowered by their respective Governments, agreed upon a supplementary protocol, which is as follows: 3AND WHEREAS the parties to the said convention of 24th of June, 1910, haveby common accord, in conformity with Article II thereof, enlarged the saidInternational Boundary Commission by the addition for the purposes of theconsideration and decision of the aforesaid difference of a third commissioner, viz :Eugene Lafleur, one of His Britannic Majesty's counsel, doctor of civil lawand former professor of international law at McGill University, who, togetherwithAnson Mills, brigadier-general of the United States Army (retired), memberof the American Geographical Society, American Commissioner of the International Boundary Commission, andFernando Beltrân y Puga, civil engineer, Mexican commissioner of theInternational Boundary Commission, member of the Geographical Society ofMexico and of the American Geographical Society, member of the Society ofCivil Engineers and Architects of Mexico,Have been constituted as a commission for the decision as to whether theinternational title to the Chamizal tract is in the United States of America orin the United States of Mexico.12Papers relating to Foreign Relations of the United Slates, 1911, p. 573.See supra., p. 313.See supra, p. 314, footnote 1.

CHAMIZAL CASE3 17AND WHEREAS the agents of the parties to the said convention have duly, andin accordance with the terms of the convention, communicated to this commission their cases, countercases, printed arguments, and other documents.AND WHEREAS the agents and counsel for the parties have fully presented tothis commission their oral arguments during the sittings held at die city of ElPaso between the first assembling of die commission on die 15th May, 1911,to the close of die hearing on die 2d June, 1911.Now, dierefore, diis commission, having carefully considered die said convention, cases, countercases, printed and oral arguments, and die documentspresented by either side, after due deliberation, makes die following decisionand award:The Chamizal tract consists of about six hundred acres, and lies between dieold bed of die Rio Grande, as it was surveyed in 1852, and the present bed ofdie river, as more particularly described in article 1 of the convention of 1910.It is the result of changes which have taken place through the action of thewater upon the banks of the river causing the river to move southward intoMexican territory.With the progressive movement of the river to the south, the American cityof El Paso has been extending on the accretions formed by the action of theriver on its nordi bank, while die Mexican city of Juarez to the south hassuffered a corresponding loss of territory.By the treaties of 1848 and 1853 the Rio Grande, from a point a little higherthan the present city of El Paso, to its moudi in the Gulf of Mexico, was constituted the boundary line between the United States and Mexico.The contention on behalf of the United States of Mexico is that diis dividingline was fixed under diose treaties in a permanent and invariable manner, andconsequently that the changes which have taken place in the river have notaffected die boundary line, which was established and marked in 1852.On behalf of the United States of America it is contended diat according tothe true intent and meaning of die treaties of 1848 and 1853, if die channel ofthe river changes by gradual accretion, the boundary follows the channel, anddiat it is only in case of a sudden change of bed that the river ceases to be theboundary, which then remains in the abandoned bed of the river.It is furdier contended on behalf of die United States of America that by theterms of a subsequent boundary convention in 1884 rules of interpretation wereadopted which became applicable to all changes in the Rio Grande which haveoccurred since die river became the international boundary, and diat thechanges which determined die formation of the Chamizal tract are changesresulting from slow and gradual erosion and deposit of alluvion within themeaning of diat convention and consequently changes which left die channelof die river as die international boundary line.The Mexican- Government, on die odier hand, contends diat the Chamizaltract having been formed before die coming in force of die convention of 1884,that convention was not retroactive and could not affect die tide to die tract,and furdier contends diat, even assuming die case to be governed by die convention of 1884, die changes in the channel have not been die result of slow andgradual erosion and deposit of alluvion.Finally die United States of America have set up a claim to the Chamizaltract by prescription, alleged to result from the undisturbed, uninterrupted, andunchallenged possession of die territory since the treaty of 1848.In 1889 die Governments of die United States and of Mexico, by a convention, created the International Boundary Commission for the purpose of carryingout the principles contained in die convention of 1884 and to avoid diedifficul-

318MEXICO/UNITED STATESties occasioned by the changes which take place in the bed of the Rio Grandewhere it serves as the boundary between the two Republics, and for otherpurposes enumerated in Article I of die convention of 1889.At a session of the boundary commissioners held on the 28th September, 1894,the Mexican commissioner presented the papers in a case known as " ElChamizal No. 4 ". These included a complaint made by Pedro Ignacio Garcia,who alleged, in substance, that he had acquired certain property formerly lyingon the south side of the Rio Grande, known as El Chamizal, which, in consequence of the abrupt and sudden change of current of die Rio Grande, wasnow on the north side of die river and within the limits of El Paso, Texas. Thisclaim was examined by the International Boundary Commissioners, who heardwitnesses upon the facts, and who, after consideration, were unable to cometo any agreement, and so reported to their respective Governments.As a result of this disagreement the convention of 24th June, 1910, was signed,and the decision of the question was submitted to the present commission.FIXED LINE THEORYArticle V of the treaty of Guadalupe Hidalgo of 1848 provides for a boundarybetween the United States and Mexico in the following terms :The boundary line between the two Republics shall commence in the Gulfof Mexico, three leagues from land, opposite die mouth of the Rio Grande,otherwise called Rio Bravo del Norte, or opposite the mouth of its deepestbranch, if it should have more than one branch emptying directly into the sea;from thence, up the middle of that river, following the deepest channel, whereit has more dian one, to the point where it strikes the southern boundary ofNew Mexico; thence, westwardly, along the whole southern boundary of NewMexico (which runs north of the town called Paso) to its western termination;thence northward, along the western line of New Mexico until it intersects thefirst branch of die river Gila (or if it should not intersect any branch of thatriver, then to the point on the said line nearest to such branch, and thence ina direct Une to the same) ; thence down the middle of the said branch and of thesaid river, until it empties into the Rio Colorado; thence, across the RioColorado, following the division line between Upper and Lower California,to the Pacific Ocean.The southern and western limits of New Mexico, mentioned in this article,are diose laid down in the map entitled " Map of the United Mexican States, asorganized and defined by various acts of the Congress of said Republic, and constructedaccording to the best authorities. Revised edition. Published at New York in 1847 byJ. Disturnell " ; of which map a copy is added to this treaty, bearing the signatures and seals of the undersigned plenipotentiaries. And, in order topreclude all difficulty in tracing upon the ground the limit separating Upperfrom Lower California, it is agreed.that the said limit shall consist of a straightline, drawn from the middle of the Rio Gila, where it unites with die Colorado,to a point on die coast of the Pacific Ocean, distant one marine league due southof the southernmost point of die port of San Diego, according to the plan ofsaid port made in the year 1782 by Don Juan Pantoja, second sailing masterof the Spanish fleet, and published at Madrid in the year 1802 in the atlas tothe voyage of die schooners Sutil and Mexicana, of which plan a copy is hereuntoadded, signed and sealed by the respective plenipotentiaries.In order to designate the boundary line with due precision upon authoritativemaps, and to establish upon the ground landmarks which shall show the limitsof bodi Republics, as described in the present article, the two Governmentsshall each appoint a commissioner and a surveyor, who, before die expiration

CHAM1ZAL CASE3 19of one year from the date of the exchange of ratifications of this treaty, shallmeet at the port of San Diego and proceed to run and mark the said boundaryin its whole course to the mouth of the Rio Bravo del Norte. They shall keepjournals and make out plans of their operations, and the result agreed upon bythem shall be deemed a part of this treaty, and shall have the same force as ifit were inserted therein. The two Governments will amicably agree regardingwhat may be necessary to these persons, and also as to their respective escorts,should such be necessary.The boundary line established by this article shall be religiously respected byeach of the two Republics, and no change shall ever be made therein, exceptby the express and free consent of both nations, lawfully given by the GeneralGovernment of each, in conformity with its own constitution.The fluvial portion of the boundary called for by the above treaty, in so faras the Rio Grande is concerned, extending from its mouth to the point whereit strikes the southern boundary of New Mexico, appears to have been fixedby the surveys of the International Boundary Commission in 1852.In 1853, in consequence of a dispute as to the land boundary and the acquisition of a portion of territory now forming part of New Mexico and Arizona,known as the " Gadsden Purchase ", the boundary treaty of 1853 was signed,the first article of which deals with the boundary as follows :The Mexican Republic agrees to designate the following as her true limitswith the United States for the future : Retaining the same dividing line betweenthe two Californias as already defined and established, according to the fiftharticle of the treaty of Guadalupe Hidalgo, the limits between the two Republicsshall be as follows : Beginning in the Gulf of Mexico, three leagues from land,opposite the rrouth of the Rio Grande, as provided in the fifth article of thetreaty of Guadalupe Hidalgo; thence, as defined in the said article, up themiddle of that river to the point where the parallel of 31 47' north latitudecrosses the same; thence due west 100 miles; thence south to the parallel of31 20', north latitude; thence along the said parallel of 31 20' to the 111thmeridian of longitude west of Greenwich ; thence in a straight line to a pointon the Colorado River 20 English miles below the junction of the Gila andColorado Rivers; thence up the middle of the said river Colorado until itintersects the present line between the United States and Mexico.For the performance of this portion of the treaty, each of the two Governments shall nominate one commissioner, to the end that, by common consent,the two thus nominated, having met in the city of Paso del Norte, three monthsafter the exchange of the ratifications of this treaty, may proceed to surveyand mark out upon the land the dividing line stipulated by this article, whereit shall not have already been surveyed and established by the mixed commission, according to the treaty of Guadalupe, keeping a journal and makingproper plans of their operations. For this purpose, if they should judge itnecessary, the contracting parties shall be at liberty each to unite to its respective commissioner, scientific or other assistants, such as astronomers and surveyors, whose concurrence shall not be considered necessary for the settlementand ratification of a true line of division between the two republics ; that lineshall be alone established upon which the commissioners may fix, their consentin this particular being considered decisive and an integral part of this treaty,without necessity of ulterior ratification or approval, and without room forinterpretation of any kind by either of the parties contracting.The dividing line thus established shall, in all time, be faithfully respectedby the two Governments, without any variation therein, unless of the express

320MEXICO/UNITED STATESand free consent of the two, given in conformity to the principles of the law ofnations, and in accordance with the constitution of each country, respectively.In consequence, the stipulation in the fifth article of the treaty of Guadalupeupon the boundary line therein described is no longer of any force, wherein itmay conflict with that here established, the said line being considered annulledand abolished wherever it may not coincide with the present, and in the samemanner remaining in full force where in accordance with the same.The treaty of Guadalupe Hidalgo, signed on the 2d February, 1848, providesthat the boundary line between the two Republics from the Gulf of Mexicoshall be the middle of the Rio Grande, following the deepest channel, where ithas more than one, to the point where it strikes the southern boundary of NewMexico. It is conceded on both sides that if this provision stood alone it wouldundoubtedly constitute a natural, or arcifinious, boundary between the twonations and that according to well-known principles of international law thisfluvial boundary would continue, notwithstanding modification of the courseof the river caused by gradual accretion on the one bank or degradation on theother bank; whereas if the river deserted its original bed and forced for itself anew channel in another direction the boundary would remain in the middleof the deserted river bed. It is contended, however, on behalf of Mexico, thatthe provisions in the treaty providing for a designation of the boundary linewith due precision, upon authoritative maps, and for establishing upon thegrounds landmarks showing the limits of both Republics, and the direction tocommissioners and surveyors to run and mark the boundary in its full courseto the mouth of the Rio Grande, coupled with the final stipulation that theboundary line thus established should be religiously respected by the two Republics, and no change should ever be made therein, except by the express andfree consent of both nations, takes this case out of the ordinary rules of international law, and by a conventional agreement converts a natural, or arcifinious,boundary into an artificial and invariable one. In support of this contentioncopious references have been made to the civil law distinguishing between landswhose limits were established by fixed measurements (agri limitati) and arcifinious lands, which were not so limited {agri arcifinii). These two classes oflands were sometimes contrasted by saying that arcifinious lands were thosewhich had natural boundaries, such as mountains and rivers, while limitedestates were diose which had fixed measurements. As a consequence of thisdistinction the Roman law denied the existence of the right of alluvion in favorof the limited estates which it was the custom to distribute among die Romangenerals, and subsequently to the legionaries, out of conquered territory. Thisrestriction of the ordinary rights appurtenant to riparian ownership is, however,considered by the best authorities to have been an exceptional provisionapplicable only to the case above mentioned, and one of the principal authoritiesrelied on by the Mexican counsel ('A. Plocquo, Legislation des eaux et de la navigation, vol. 2, p. 66) clearly establishes that the mere fact that a riparian proprietor holds under a title which gives him a specified number of acres of landdoes not prevent him from profiting by alluvion. The difficulty in this casedoes not arise from the fact that the territories in question are established byany measurement, but because the boundary is ordered to be run and markedalong the fluvial portion as well as on the land, and on account of the furtherstipulation that no change shall ever be made therein. Do these provisionsand expression, in so far as they refer to the fluvial portion of the boundary,convert it into an artificial boundary which will persist notwithstanding allchanges in the course of the river? In one sense it may be said that the adoptionof a fixed and invariable Une, so far as the river is concerned, would not be a

CHAMIZAL CASE321perpetual retaining of the river boundary provided for by the treaty, and wouldbe at variance with the agreement of the parties that the boundary shouldforever run in the middle of the river. The direction as to marking the courseof the river as it existed at the time of the treaty of 1848 is not inconsistent witha fluvial line varying only in accordance with the general rules of internationallaw, by erosion on one bank and alluvial deposits on the other bank, for thismarking of the boundary may serve the purpose of preserving a record of theold river bed to serve as a boundary in cases in which it cuts a new channel.Numerous treatie

Chamizal Arbitration, Arguments, Case and Countercase of the United States of America . . ., Washington, 1911 (5 volumes) Chamizal Arbitration, United States and Mexico, minutes of the meetings of the International Boundary Commission, June 10 and 15, 1910, containing the award in the Chamizal Case, Washington, 1911.