Maya Brehm is a researcher in weapons law at the Geneva Academy of International Humanitarian Law and Human Rights (ADH) and a consultant with Article 36 and PAX. Her recent work focuses on the humanitarian impact of explosive weapon use in populated areas and on framing the policy debate on autonomous weapons systems.
In a recently published report, Human Rights Watch (HRW) documents harm to civilians from the use of 122mm Grad rockets apparently fired by Ukrainian government forces and pro-government militias into Donetsk and its suburbs. In four attacks investigated by HRW at least 16 civilians were killed and many more wounded. According to HRW insurgent forces also recently used Grad rockets. The image below from HRW shows attacks in and around Donetsk (click to enlarge). The organization has also posted a video online presenting its findings.
The problem with Grad rockets
Grad rockets are unguided rockets fired from a multiple-barrel rocket launcher (MBRL) that can deliver up to 40 rockets within a very short time to a range of 20 kilometers. Like other unguided, indirect fire weapons, Grad rockets are considered ‘area weapons’, suited for attacks against targets of significant dimensions, because due to ballistic and other factors, the area over which the rockets can spread out is relatively wide.
The dimension of the area affected by a rocket attack (the area of potential impact of the rockets combined with the blast/fragmentation zones of the individual rockets) is a function of many variables, including fuzing, ballistic and firing technique-related factors. As that area can be very wide, the use of Grad rockets in populated areas carries a high risk of harm to civilians.
An indiscriminate weapon?
The remarkable aspect of this HRW report is that it goes beyond the usual exhortations on parties to a conflict to fully comply with the rules of international humanitarian law (IHL), and calls on ‘all parties to the conflict in eastern Ukraine, particularly Ukrainian government forces, to stop using Grad rockets in or near populated areas because of the likelihood of killing and wounding civilians.’ HRW considers that
Grad rockets cannot be targeted with sufficient precision to differentiate military targets … from civilians and civilian structures…, which are immune from attack. As such, their use in populated areas violates the laws-of-war prohibition against indiscriminate attacks.
IHL experts will be quick to point out that Grad rockets are not specifically prohibited under treaty law. What is prohibited under customary IHL is the use of ‘weapons which are by nature indiscriminate’ (Rule 71, ICRC, Customary IHL study, 2005). There is, however, no agreement on what weapons concretely, if any, should be deemed ‘indiscriminate weapons’ whose use would be prohibited on this basis.
According to the ICRC, the two criteria most frequently cited to determine what is an indiscriminate weapon are ‘whether the weapon is capable of being targeted at a military objective and whether the effects of the weapon can be limited as required by international humanitarian law’. These criteria are drawn from the prohibition on indiscriminate attacks, which are described in Article 51(4) of 1977 Additional Protocol I to the Geneva Conventions.
The prohibition on indiscriminate attacks is, however, silent on what means of combat are deemed sufficiently dirigible or limited in their effects. In its customary IHL study, the ICRC notes that weapons cited in practice as being indiscriminate in certain or all contexts include Scud missiles and Katyusha rockets. The Grad, the most widely used multiple barrel rocket launcher in the world, is not mentioned.
Indeterminacy and case-by-case assessments
According to the dominant doctrinal view a weapon that can be used in compliance with IHL in some circumstances cannot be deemed indiscriminate per se (or ‘inherently’ indiscriminate). This view is premised on the proposition that we can distinguish between ‘inherent’ characteristics of a weapon that make it impermissibly difficult to direct, on the one hand, and characteristics pertaining to a weapon’s use, on the other hand.
But because the legal assessment of whether a given weapon can be directed as required by IHL is treated as context-dependent it has proven difficult in practice to agree that specific weapons are illegal per se. Proponents of a weapon will usually be able to come up with a scenario in which a weapon’s use would likely not result in an indiscriminate attack (e.g. an attack on a large military objective in an area devoid of civilians).
In the absence of a weapon-specific treaty that resolves the indeterminacy of the general rules, therefore, we are unable to determine the legality of a weapon. This, of course, ‘is tantamount to saying that States consider the general principle on indiscriminate weapons to have become valueless’. (A. Cassese, ‘The Prohibition of Indiscriminate Means of Warfare’, in A. Cassese, P. Gaeta and S. Zappalà (Eds.), The Human Dimension of International Law: Selected Papers of Antonio Cassese, 2008.)
What we are left with are case-by-case (attack-by-attack) assessments, which are not ideally suited to draw more categorical lines. The Gotovina case (IT-06-90) before the ICTYa ruling that was meant to shape the law pertaining to artillery use against targets in populated areas, grappled with these issues and has left a dangerous legacy.
An attempt at drawing a line
Gotovina, a Croatian commander, was prosecuted before the ICTY, inter alia, for crimes committed in connection with the shelling, among other weapons with 122mm Grad rockets, of several towns, including Knin. (For detailed discussions, see the articles by Clark, Huffmann, and Vallentgoed.)
The Trial Chamber, considering a variety of factors, determined that although ‘MBRLs are generally less accurate than Howitzers or mortars, their use by the HV [Croatian army] in respect of Knin on 4 and 5 August 1995 was not inherently indiscriminate’. (§1897, Gotovina et al., ICTY Trial Chamber Judgment, 15 April 2011.)
As it was contested what had actually been targeted in all cases (there were indications of ‘area bombardment’), the Trial Chamber decided, with respect to a sub-set of all projectile impact sites under consideration, that projectiles that impacted within a distance of 200 meters of an identified artillery target, were presumed to have been fired at that target, whereas impact sites further away were treated as indicators of an unlawful attack on civilians. (§1898)
This approach was rejected on appeal, which caused the rest of the case to collapse and led to the reversal of the convictions.
Gotovina’s legacy: the end of indiscriminate attacks?
The Appeals Chamber dismissed the 200 meter ‘margin of error’ among other reasons on the ground that firing a weapon from a greater distance could well have resulted in shells and rockets impacting more than 200 meters away from a target. The wide spread of impact sites could then be plausibly explained by a higher margin of error, and it could not be excluded that the shells were all aimed at legitimate military targets. (§§60-65, Gotovina et al., ICTY, Appeals Chamber Judgment, 16 November 2012.)
This line of argument is also evidenced in expert reports submitted by the Defence on appeal. Lieutenant General (ret.) Shoffner, for example, rejected the 200 meter standard on the basis that under the given firing conditions, more than 50% of the rockets could be expected to fall more than 300 meters from the aim point. (Appellant Ante Gotovina’s motion to admit new evidence pursuant to Rule 115 (Public redacted version), 4 November 2011, Exhibit 21, 3540.)
That the Majority of the Appeals Chamber subscribed to this logic bodes ill for the protection of civilians in populated areas from the effects of explosive weapons. As Judge Agius pointed out in his dissenting opinion, the approach makes it impossible to classify any attack as indiscriminate in the absence of an established margin of error. (§21, Dissenting Opinion of Judge Agius, Gotovina et al., ICTY, Appeals Chamber Judgment, 16 November 2012.)
The Trial Chamber had clearly realized this. In a footnote, it noted that
had these impacts which were at a distance of up to 700 metres from artillery targets been the result of the inaccuracy of the artillery weapons used, that would require a further consideration of whether such inaccurate weaponry can be used in the context of an artillery attack on specific targets within a town. (Gotovina et al., ICTY Trial Chamber Judgment, 15 April 2011, footnote 932.)
The Appeals Chamber, however, did not give further consideration to this matter, and it has been criticized for its ‘apparent disregard for the consequences’ of its ruling.
Toward a presumption against wide-area effects explosive weapons in populated areas
Can Grad rockets impacting in residential areas of Ukrainian towns now simply be justified by reference to the relative inaccuracy of the rocket system, and the large distance they were fired from? I certainly hope not.
In the Gotovina case, several artillery experts invited by the Prosecution to comment on the Defence reports did not think that the use of Grad rockets was appropriate in populated areas (even though they also rejected the 200 meter standard as too simplistic). Lieutenant General (ret.) Applegate, for example, considered that the use of MRL systems in built-up areas was surprising in view of the wide dispersal of their rockets. He pointed out ‘that the MLRS rocket system – a superior system to that used by the HV … was not deployed to support UN forces in Bosnia because of its inherently larger spread of fire and lack of discrimination when engaging targets in built-up areas occupied by non-combatants.’ (Notice of Filing of Public Redacted Version of Prosecution Response to Gotovina’s Second Rule 115 Motion, and Request for Change in Status of Corrigendum, Public Annex I, 5678.)
The Gotovina case illustrates that artillery experts, even if broadly in agreement on questions of targeting doctrine and weaponeering, can come to opposite conclusions about the appropriateness and acceptability of using Grad rockets and other explosive weapons in a populated area. The answer to what is permissible is not going to be settled on the basis of ‘error margins’ alone.
The law provides the corner posts: to protect civilians from harm, attackers must ensure that their weapons can be and are directed at a specific military objective and that their effects are limited. Rather than deferring to indeterminate legal rules or determinations on an attack-by-attack basis, a more categorical determination of what explosive weapons are acceptable and ultimately permissible for use in a populated area can and must be made.
Grad rockets, typically used for their capacity to affect a wide area at great range, have been shown in a number of conflicts to result in unacceptably high levels of harm to civilians when fired into a populated area. (See, e.g. the Report of the Independent International Fact Finding Mission in Georgia, Vol. II, 2009, 338-343; AOAV, Syria’s Dirty Dozen: The Grad, 2013.) A categorical presumption against the use, in populated areas, of Grad rockets and other explosive weapons with wide area effects (due to low accuracy of delivery, high dispersal and/or large blast/fragmentation radius) can help prevent and reduce harm to civilians.