Related Rule
United States of America
Practice Relating to Rule 86. Blinding Laser Weapons
The US Naval Handbook (1995) states:
Directed energy devices, which include laser … are not proscribed by the law of armed conflict. Lasers may be employed as a range finder or for target acquisition with the possibility of ancillary injury to enemy personnel, or directly against combatants as an anti-personnel weapon. Their use does not violate the prohibition against the infliction of unnecessary suffering. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), pp. 452–454, § 9.8.
The Annotated Supplement to the US Naval Handbook (1997) states that the position defined in the Naval Handbook
is no longer completely accurate with respect to antipersonnel weapons. There have been various efforts over the years to prohibit the use of lasers as antipersonnel weapons … [The 1995] Protocol IV [to the Convention on Certain Conventional Weapons] prohibits the use or transfer of laser weapons specifically designed to cause blindness to unenhanced vision. 
United States, Annotated Supplement to the Naval Handbook, 1997, § 9.8, footnote 45.
The US Naval Handbook (2007) states: “U.S. military forces will not employ laser weapons specifically designed to cause permanent blindness.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 9.8.
Prior to the adoption of the 1995 Protocol IV to the Convention on Certain Conventional Weapons, the United States was developing a number of laser systems intended to blind either personnel and/or optical systems. An evaluation in 1988 by the Office of the Judge Advocate General concluded that such weapons would not cause unnecessary suffering and therefore would not be illegal. 
United States, Department of the Army, Office of the Judge Advocate General, Memorandum on Use of Lasers as Antipersonnel Weapons, Doc. DA PAM 27-50-191, 29 September 1988, reprinted in The Army Lawyer, November 1988, p. 3.
During the meetings of governmental experts preparatory to the Review Conference, the United States opposed the adoption of a Protocol on the subject. The system that was closest to deployment was the “Laser Countermeasure System” (LCMS also referred to as the PLQ-5), mounted on an M16 rifle, for which the army hoped to have government approval for manufacture in June 1995. This system was described as having “the primary objective to detect, jam and suppress threat fire control, optical and electro-optical systems”. 
Lockheed-Sanders Fact Sheet, Laser Countermeasure System (LCMS), Doc. AN/PLQ-5, 1994.
It certainly had the capacity to blind at considerable distances and its use for this purpose was not excluded. 
United States, Department of the Army, Office of the Judge Advocate General, Memorandum on the subject AN/PLQ-5 Laser Countermeasure System, Law of War Review, 16 September 1994.
Congress decided to delay its decision on whether to give approval for manufacture. 
Human Rights Watch Arms Project, US Blinding Laser Weapons, 21 May 1995, New York/Washington D.C., Vol. 7, No. 5, pp. 2 and 9; Inside the Pentagon, 13 July 1995, p. 9.
As a result of pressure from a number of Congressmen, 
United States, Letter to the Secretary of Defense from 48 US Senators and Congressmen, 31 July 1995.
the Department of Defense reconsidered its policy. In September 1995, the Secretary of Defense announced that “the Department of Defense prohibits the use of lasers specifically designed to cause permanent blindness of unenhanced vision and supports negotiations prohibiting the use of such weapons”. 
United States, Defenselink News Release No. 482-95, 1 September 1995. (The US Secretary of Defense repeated the same statement on 17 January 1997, SECDEF Memo U00888/97, DoD Policy on Blinding Lasers.)
A Department of Defense News Briefing in October 1995 stated:
With lasers, we have an opportunity to stop a proliferation of a new and dangerous weapon, we hope. We are now engaged in discussions at the Conference on Conventional Weapons in Vienna to do just that. Secretary Perry felt strongly that we should take a lead role in that by swearing off the development and use of lasers intentionally designed to blind people. 
United States, Defenselink Transcript, DoD News Briefing, Mr. Kenneth H. Bacon, ASTD (PA), 12 October 1995.
A controversial analysis of the 1995 Protocol IV to the Convention on Certain Conventional Weapons by the Judge Advocate General of the US Department of the Army in 1995 stated that the Protocol was only applicable in international armed conflict, and not in operations such as “non-combatant evacuation, peacekeeping or counter terrorism missions, or in internal conflicts”. It also stated that the “State Parties that negotiated and adopted (by consensus) the laser Protocol did not conclude that use of a laser to blind an enemy combatant causes unnecessary suffering, or that use of a laser to blind an individual enemy combatant was illegal”. 
United States, Department of the Army, Office of the Judge Advocate General, Memorandum on Effect of Laser Protocol on U.S. Army Programs, 1 November 1995, US Airforce Operations Law Deskbook, Vol. II, 1996, p. IX-14, §§ 4(d) and 5.
Further to concern expressed at this interpretation by a US Senator, 
United States, Letter from Senator Patrick Leahy to the Secretary of Defense, 18 April 1996.
the Secretary of Defense replied:
Regretting any confusion created by the internal November 1995 memo, I would like to take this opportunity to reaffirm the Department’s policy. As you know, it is US policy to prohibit the use of weapons specifically designed to permanently blind … It was not the intent of the States Parties to Protocol IV to prohibit only mass blinding … As you note, there is no prohibition in [the Convention on Certain Conventional Weapons] on research, development or production. Nevertheless, the Department has no intent to spend money developing weapons we are prohibited from using. We certainly would not want to encourage other countries to loosely interpret the treaty’s prohibitions, by implying that we want to develop or produce weapons we are prohibited from using … On the question of individual blinding, your interpretation is correct. Under both [the Convention on Certain Conventional Weapons] and [Department of Defense] policy, laser weapons designed specifically to cause permanent blindness may not be used against an individual enemy combatant. 
United States, Letter from the Secretary of Defense to Senator Patrick Leahy, 8 May 1996.
On 5 October 1995, namely after the adoption of new policy and during the final negotiations of Protocol IV to the Convention on Certain Conventional Weapons, the US army cancelled the Laser Countermeasure System (LCMS) programme. 
Bradley Graham, “Army Laser Weapon Becomes First Casualty of New Policy”, Washington Post, 13 October 1995; “Army finalizing LCMS termination plan”, Inside the Pentagon, 19 October 1995.
During the final plenary session of the First Review Conference of States Parties to the Convention on Certain Conventional Weapons (Second Session) in 1996, the United States stated that it “supported expansion of the scope of Protocol IV and it is the policy of the US to refrain from the use of laser weapons prohibited by Protocol IV at all times”. 
United States, Statement at the First Review Conference of States Parties to the Convention on Certain Conventional Weapons (Second Session), 3 May 1996, reprinted in W. Hays Parks, “Memorandum of Law: Travaux préparatoires and legal analysis of blinding laser weapons protocol”, The Army Lawyer, June 1997, p. 41.
The guidelines on blinding laser weapons issued in 1997 by the US Secretary of Defense state:
The Department of Defense prohibits the use of lasers specifically designed to cause permanent blindness and supports negotiations to prohibit the use of such weapons. However, laser systems are absolutely vital to our modern military. Among other things, they are currently used for detection, targeting, range-finding, communications and target destruction. They provide a critical technological edge to US forces and allow our forces to fight, win and survive on an increasingly lethal battlefield. In addition, lasers provide significant humanitarian benefits. They allow weapon systems to be increasingly discriminate, thereby reducing collateral damage to civilian lives and property. The Department of Defense recognizes that accidental or incidental eye injuries may occur on the battlefield as the result of the use of lasers not specifically designed to cause permanent blindness. Therefore, we continue to strive, through training and doctrine, to minimize these injuries. 
United States, Secretary of Defence, DOD Policy on Blinding Lasers, SECDEF Memo U00888/97, 17 January 1997, reprinted in Annotated Supplement to the Commander’s Handbook on the Law of Naval Operations, prepared by the Oceans Law and Policy Department, Center for Naval Warfare Studies, Naval War College, Newport, Rhode Island, November 1997, § 9.8, footnote 45.
In 1997, in his message to the US Senate transmitting the 1995 Protocol IV to the Convention on Certain Conventional Weapons for consent to ratification, the US President stated: “These blinding lasers are not needed by our military forces. They are potential weapons of the future, and the US is committed to preventing their emergence and use.” Regarding the scope of the Protocol, whilst recognizing that it was officially that of international armed conflicts, the same message indicated that “it is US policy to apply the Protocol to all such conflicts, however they may be characterized, and in peacetime”. 
United States, Message from the US President transmitting Protocols II, III and IV to the Convention on Certain Conventional Weapons to the Senate for consent to ratification, Treaty Doc. 105-1, Washington D.C., 1997, Letter of Transmittal, p. IV and Tab.(C), p. 4.
The Annotated Supplement to the US Naval Handbook (1997) states:
While blinding as an incidental effect of “legitimate military employment” of range finding or target acquisition lasers is not prohibited by [the 1995 Protocol IV to the Convention on Certain Conventional Weapons], parties thereto are obligated “to take all feasible precautions” to avoid such injuries. 
United States, Annotated Supplement to the Commander’s Handbook on the Law of Naval Operations, prepared by the Oceans Law and Policy Department, Center for Naval Warfare Studies, Naval War College, Newport, Rhode Island, November 1997, § 9.8, footnote 45.
The US Naval Handbook (2007) states:
Directed-energy devices, such as laser … are not proscribed by the law of armed conflict. Lasers may be employed as a rangefinder or for target acquisition, despite the possibility of incidental injury to enemy personnel. Laser “dazzlers” designed to temporarily disorient may also be employed. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 9.8.
In 1995, in a US Department of Defense policy statement on blinding lasers, the need for some restrictions, aside from the prohibition of deliberate blinding, was explained thus:
Laser systems are absolutely vital to our modern military. Among other things, they are currently used for detection, targeting, range-finding, communications and target destruction. They provide a critical technological edge to US forces and allow our forces to fight, win and survive on an increasingly lethal battlefield. In addition, lasers provide significant humanitarian benefits. They allow weapons systems to be increasingly discriminate, thereby reducing collateral damage to civilian lives and property. The Department of Defense recognizes that accidental or incidental eye injuries may occur on the battlefield as the result of the use of legitimate laser systems. Therefore we continue to strive, through training and doctrine, to minimize these injuries. 
United States, Defenselink News Release, Reference Number: 482-95, 1 September 1995.