Concept and principle of equality of arms
Die Equality of arms is a fundamental principle of the rule of law, which is of central importance particularly in civil procedure law, criminal procedure law, and administrative proceedings. The term refers to the right of parties involved in proceedings to participate in the process with equal procedural opportunities. The aim of equality of arms is to ensure a fair, balanced, and impartial procedure by granting all parties — especially litigants in a court case — equal opportunities to enforce and defend their legal positions.
Historical development
The principle of equality of arms has its roots in the general principle of equality and the concept of fair proceedings, which have been refined throughout history in numerous legal systems. In modern times, the principle was initially recognized as an element of a ‘fair trial’, especially through the case law of constitutional courts and the European Court of Human Rights, and subsequently developed further.
Equality of arms in the legal system
National legal foundations
German law
In German law, equality of arms is derived in particular from fundamental rights — such as the principle of equality (Art. 3 Basic Law) and the right to be heard in court (Art. 103 para. 1 Basic Law). It is a cornerstone of the legal process system.
Austrian and Swiss law
In Austria and Switzerland, equality of arms is likewise constitutionally protected, for example through the European Convention on Human Rights (ECHR) and corresponding provisions of the respective constitutions.
International legal foundations
European Convention on Human Rights (ECHR)
The ECHR guarantees the right to a fair trial in Art. 6 para. 1. According to the case law of the European Court of Human Rights, equality of arms is defined as an essential element of this guarantee.
International Covenant on Civil and Political Rights
The International Covenant on Civil and Political Rights (ICCPR) likewise safeguards in Art. 14 the right to equality of parties and to a fair trial.
Areas of application for equality of arms
Civil procedure law
In civil proceedings, equality of arms guarantees the parties equal opportunities to present their case, submit evidence, and make motions. Impermissible or unfounded privileges for one party are inadmissible. This particularly applies to access to case files, preparation of pleadings, and the setting of deadlines and taking of evidence.
Criminal procedure law and criminal proceedings
In criminal proceedings, the principle of equality of arms protects the rights of the defense. The prosecution and the defense — for example, the accused — must be able to demonstrate the same opportunities to submit motions for evidence, name witnesses, and request or discuss evidence. Notably, law enforcement authorities are obligated to consider and disclose exculpatory circumstances as well as incriminating ones.
Administrative proceedings
Equality of arms also guarantees in administrative proceedings that parties have the right to inspect files and receive information, and can present their views on an equal footing. Authorities may not favor or disadvantage any party. This applies, for example, in hearings or when granting legal remedies.
Forms and practical significance
Right to file inspection and information
Equality of arms encompasses the right of each party to inspect the case files. Irrespective of the area of law, all parties must be granted access to the same information to be able to effectively assert their rights.
Equal access to evidence and witnesses
The right to summon witnesses or submit evidence must be equally available to all parties involved in proceedings. Impermissible restrictions or structural preferences for individual parties are incompatible with the principle.
Right to be heard
It follows directly from the principle of equality of arms that every party to a proceeding must be given the opportunity to fully and equally express themselves on all key points relevant to the case.
Limits of the principle
Superior resources
Equality of arms does not imply complete material equality outside of procedural law. The legal principle cannot fully compensate for differences in financial or organizational resources between the parties — for example, between a private individual and a large corporation; its main use is procedural equality.
Necessary exceptions
Certain statutory special regulations may be justified for reasons of the common good and may require deviations from the ideal of equality of arms in individual cases (e.g. protection of witness protection programs, duties of confidentiality).
Legal consequences of a violation of equality of arms
A violation of the principle of equality of arms can have serious legal consequences. In such cases, courts may identify procedural errors, annul unlawful decisions, or refer the case back for rectification. In extreme cases, there is also the possibility of a constitutional complaint or an individual application to the European Court of Human Rights.
Significance in case law
National and international case law accord great significance to the principle of equality of arms. Numerous decisions emphasize that fair proceedings are inconceivable without equality of procedural means. Especially in criminal and asylum proceedings, but also in complex civil proceedings, there are regular references and concrete examinations regarding equality of arms.
Summary and outlook
Equality of arms is an indispensable element of any rule-of-law procedure. It serves to secure procedural equality of opportunity and ensures that every participant can effectively exercise their rights. In the ongoing development of procedural rules and the digitization of legal proceedings, consistent respect for this principle remains of central importance for trust in the legal system and the protection of individual legal positions.
Frequently asked questions
What practical significance does the principle of equality of arms have in civil proceedings?
The principle of equality of arms plays a central practical role in civil proceedings. It ensures that both parties in a legal dispute receive the same opportunity to properly and comprehensively present their claims and means of defense before the court. Accordingly, no unilateral procedural advantages may be created or permitted that would impermissibly strengthen the position of one party. This includes, among other things, equal access to information and evidence, the right to be heard, and entitlement to a fair process. Equality of arms is especially relevant in the relationship between parties represented by counsel and those unrepresented: The court must ensure that an unrepresented party is informed of necessary procedural steps, to prevent disadvantages resulting from lack of legal knowledge, without crossing the line into impermissible partisanship. Ultimately, the principle serves to ensure a fair proceeding in line with Art. 103 para. 1 Basic Law and Art. 6 ECHR.
How is the principle of equality of arms specifically implemented in criminal proceedings?
In criminal proceedings, equality of arms is manifested above all in the duty of the court and prosecuting authorities to grant the accused all necessary opportunities to exercise their rights of defense. This specifically includes the right to inspect files (Section 147 German Code of Criminal Procedure), which enables the defense counsel or accused to obtain full information on the status of the proceedings and the available evidence. Equality of arms also includes the accused’s and defense counsel’s right to question witnesses and to make motions for evidence and participate in interrogations. Furthermore, incriminating and exculpatory evidence must be treated equally; the so-called ‘fair trial’ principle under Art. 6 para. 1, 3 ECHR must be observed. This balance becomes critical, for example, in detention cases where time or organizational restrictions could impair defense rights; courts and authorities must pay particular attention to balancing the procedural rights of both sides.
Are there specific requirements for equality of arms in administrative proceedings?
Administrative proceedings require special attention to equality of arms, as one party is typically an authority and the other a citizen, which can lead to structural imbalances. Courts are therefore obligated, in particular, to provide inexperienced citizens with guidance and judicial support so that they have the same opportunities as an authority familiar with administrative law. From this arises the duty of care pursuant to Section 86 para. 3 Code of Administrative Court Procedure, according to which the court must work to supplement incomplete party submissions to ensure true equality of opportunity. This covers both the submission of evidence and the legal assessment of the claim. All these measures aim to prevent a party from being procedurally disadvantaged solely due to an informational or structural advantage held by the administration.
How does equality of arms affect the composition of the court and the selection of expert witnesses?
Equality of arms requires that the composition of the court is impartial and remains transparent for both parties. Courts must ensure that no person involved in the underlying facts may participate in the decision, so as to prevent any preference or disadvantage (exclusion and objection according to Sections 41 ff. Code of Civil Procedure and Sections 22 ff. Code of Criminal Procedure). The same applies to the appointment of experts: Both parties must be given the opportunity to raise objections about the expert and have the right to provide their own expert reports or comment on them. As a result, the selection and examination of experts must always be open to scrutiny by both parties to the proceedings.
What is the significance of the principle of equality of arms regarding file inspection?
The right to file inspection is a key instrument for implementing equality of arms in all types of proceedings. It allows parties to familiarize themselves with the entire file content, so they can effectively defend themselves or substantiate their case. Refusal or restriction of file inspection may only occur under strict conditions expressly provided by law (for example, to protect overriding third-party interests or procedural security, as per Sections 29, 100 Administrative Procedure Act or Section 147 Code of Criminal Procedure). Parties may still, for instance, access the essential file content through anonymized or redacted extracts in cases involving confidentiality interests. The court must ensure that no party is disadvantaged due to lack of information access.
To what extent does the principle of equality of arms extend to the law of costs and litigation funding?
Equality of arms plays a decisive role in the law of costs as well. The granting of legal aid and advisory assistance enables economically weaker parties to exercise their rights in proceedings without failing due to costs (Sections 114 ff. Code of Civil Procedure). At the same time, this prevents a party from gaining a structural advantage in the proceedings due to financial superiority. The design of legal aid is therefore a central element in maintaining equality of opportunity, especially with respect to financial resources, in access to the legal system.
What legal consequences can a violation of the principle of equality of arms entail?
A violation of the principle of equality of arms can have serious legal consequences. In civil and administrative proceedings, there is the possibility of objection and, where applicable, subsequent remedy if a party was not adequately involved in the proceedings or suffered an informational disadvantage. In serious cases, this may lead to the reversal of a judgment or the reopening of proceedings. In criminal proceedings, violation of equality of arms can constitute a procedural error that may be grounds for appeal under Section 337 Code of Criminal Procedure. Under the European Convention on Human Rights (ECHR), a complaint can be filed with the European Court of Human Rights if the ‘fair trial’ guarantee has been violated. The consequences range from delays in proceedings to retrials and even claims for damages.
