The Spanish Supreme Court is divided into five "Salas" (Divisions) ("Civil," "Penal," "Contencioso Administrativo," "Social" and "Militar") that each have a different number of judges ("magistrados"). When adjudicating cases the judges sit in "secciones" (in English, "panels"), usually of three "magistrados."

For example, "Sala de lo Penal, Sección 1ª" might be rendered as First Panel of the Criminal Division (of the Spanish Supreme Court).

In case it may be of interest for the text you're translating, here is some additional info on Spanish court terminology from my blog, comparing and contrasting Spanish terms ("sala;" "sección;" "sede;" "cámara") with related English terms (division; panel; chamber; courtroom; courthouse):

"Sala," "sección," and "sede" are used variously to describe the physical and organizational divisions of Spanish courts. When referring to the overall jurisdictional organization of courts, "sala" is perhaps best translated as “division.” For example, the Spanish Supreme Court ("Tribunal Supremo") is divided into five "salas" (or "jurisdicciones"): "Sala Primera, de lo Civil" (Civil Division); "Sala Segunda, de lo Penal" (Criminal Division); "Sala Tercera, de lo Contencioso-Administrativo" (Administrative Division); "Sala Cuarta, de lo Social" (Labor Division) and "Sala Quinta, de lo Militar" (Military Division). In this context the expression la Sala en pleno refers to a sitting of all of the judges in a given court division. And, thus, "el Pleno del Tribunal" or "el Tribunal en Pleno" denotes the “full court,” “en banc court” or “court en banc”, i.e., a session attended by all of the judges on a given court.

"Sala" can also refer to a panel of (usually three) judges who adjudicate cases. In this sense "sala" is a synonym of "tribunal," since "tribunal" may refer to a court, or to a panel of three judges. "Sección"is likewise used in this context to describe judges sitting in panels. In that regard and as an example, the Spanish Constitutional Court ("Tribunal Constitucional") may meet "en pleno" (the full court of 12 judges), in two "salas" (half-court panels of six judges), or in four "secciones" (three-judge panels).

In other respects, the expression "sala de gobierno" refers to the panel or committee of judges ("magistrados") who decide administrative and organizational matters in their respective courts (such as the "Tribunal Supremo," the "Tribunales Superiores de Justicia" in each Autonomous Community and the "Audiencia Nacional"). The duties of the "salas de gobierno" include, among others, approving case assignment rules ("normas de reparto"), nominating and appointing judges "pro tempore" ("magistrados suplentes" and "jueces de provision temporal"), and exercising the disciplinary powers ("facultades disciplinarias") vested in them in the "Ley Orgánica del Poder Judicial."

In other respects,"sala" in the expression "sala de vistas" denotes a “courtroom.” Thus, the expression "Sala de Vistas de la Sala Segunda del Tribunal Supremo" refers to a specific courtroom within the Criminal Division of the Supreme Court.

Although “chamber” is not often used to describe the jurisdictional or organizational divisions of US and English courts, many bilingual sources translate "sala" literally as “chamber,” perhaps due to the fact that it is used in several European courts in which French is an official language. For example, at the European Court of Human Rights a 7-judge panel is known as a “chamber,” while a 17-judge panel is a “Grand Chamber” ("Grande Chambre" in French). Likewise panels of three to five judges on the Court of Justice of the European Union are known as “chambers,” and its 13-judge panels are “Grand Chambers.”

In contrast, in Anglo-American jurisdictions “chambers” (always plural) is not used to denote the divisions of courts, but rather often denotes a judge’s private offices at a courthouse. Thus, an “in-chambers conference” refers to a meeting with a judge in his offices, rather than in the courtroom. By extension the Latin expression “in camera” (“in chambers”) means “in private,” and an “in camera hearing”* refers to a hearing from which the public has been excluded ("audiencia a puerta cerrada") as opposed to a “hearing in open court” or “public hearing” ("audiencia pública"). In British English “chambers” may also denote the offices of a barrister or a group of barristers.

In the context of parliamentary practice "cámara" is not “chamber,” but rather is more often rendered as “house:” "cámara alta" (upper house); "cámara baja" (lower house); "Cámara de los Lores" (House of Lords); "Cámara de los Comunes" (House of Commons), etc.

And finally, "sede" often denotes the physical location of a court, the “courthouse” itself and, depending on the context, the often seen expression "en sede judicial" may be translated as “at the court,” “in court,” “before the judge,” or simply with the adjective “judicial:” "Declaró en sede judicial" (he testified in court/before the judge); "comparecer en sede judicial" (to appear in court); "determinación de responsibilidad civil en sede judicial" (judicial determination of civil liability), etc.

By extension, if "en sede judicial" means "en el tribunal," then "en sede policial" must likewise mean "en comisaría," while "en sede parliamentaria" denotes "en el Parlamento." Although widely used in the press, this peculiar use of “en sede” has been described as a “cursilería” (Antonio Burgos, ABC, 5 July 2004) and as “abusivo y repetitivo” (Fundéu).

*With the terminology reform initiated in the Civil Procedure Act 1997, in England and Wales an "in camera hearing" is now known as a “hearing in private.”

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