First of all, that is not true.
His subordinates say he killed dozens of suspected enemy who had been captured or incapacitated in some way.
Second is that even the medic who says Gallagher failed to kill this particular suspect, admits that Gallagher tried to slit the suspect's throat to kill him, but simply failed.
Third is that taking your picture with a person you thought you just killed is really, really sick, and totally illegal.
If that is true why did the navy not convict him
Technicalities.
The one documented incident, the corpsman said that when Gallighar slit his throat, he missed the arteries, so it was not fatal.
He said he euthanized the suspect himself.
The rest were not documented enough for a conviction.
But the image is a war crime against mutilation of bodies, humiliation, abuse of the dead, etc.
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Geneva Convention IV
Article 16, second paragraph, of the 1949 Geneva Convention IV provides: “As far as military considerations allow, each Party to the conflict shall facilitate the steps taken … to protect [the killed] against … ill-treatment.”
Additional Protocol I
Article 34(1) of the 1977 Additional Protocol I provides: “The remains of persons who have died for reasons related to occupation or in detention resulting from occupation or hostilities … shall be respected”.
Additional Protocol II
Article 4 of the 1977 Additional Protocol II provides:
1. All persons who do not take a direct part or who have ceased to take part in hostilities, whether or not their liberty has been restricted, are entitled to respect for their person [and] honour …
2. Without prejudice to the generality of the foregoing, the following acts against the persons referred to in paragraph I are and shall remain prohibited at any time and in any place whatsoever:
…
(e) outrages upon personal dignity, in particular humiliating and degrading treatment …
ICC Statute
Pursuant to Article 8(2)(b)(xxi) and (c)(ii) of the 1998 ICC Statute, “[c]ommitting outrages upon personal dignity” constitutes a war crime in both international and non-international armed conflicts.
II. Other Instruments
Oxford Manual
Article 19 of the 1880 Oxford Manual provides: “It is forbidden to … mutilate the dead lying on the field of battle.”
Cairo Declaration on Human Rights in Islam
Article 3(a) of the 1990 Cairo Declaration on Human Rights in Islam provides: “In the event of the use of force and in case of armed conflict … it is prohibited to mutilate dead bodies.”
Comprehensive Agreement on Respect for Human Rights and IHL in the Philippines
Article 3(4) of Part IV of the 1998 Comprehensive Agreement on Respect for Human Rights and IHL in the Philippines provides that “desecration of the remains of those who have died in the course of the armed conflict or while under detention” shall remain prohibited at any time and in any place whatsoever with respect to persons
hors de combat. Article 4(9) provides: “Every possible measure shall be taken, without delay, … [to prevent] mutilation [the dead].”
ICC Elements of Crimes
With reference to the war crime of outrages upon personal dignity, the 2000 ICC Elements of Crimes specifies that Article 8(2)(b)(xxi) and (c)(ii) of the 1998 ICC Statute also applies to dead persons.
UNTAET Regulation No. 2000/15
The UNTAET Regulation No. 2000/15 establishes panels with exclusive jurisdiction over serious criminal offences, including war crimes. According to Section 6(1)(b)(xxi) and (c)(ii), “[c]ommitting outrages upon personal dignity” constitutes a war crime in both international and non-international armed conflicts.
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Customary IHL - Practice Relating to Rule 113. Treatment of the Dead
This is well known and no sane soldier would do what Gallaghar did.
The US prosecuted many cases of this in the past.
The fact we no longer do, condemns our whole military system.