The 7 August 2015 United Nations Security Council resolution 2235 (2015) to establish a joint investigation mechanism to identify individuals or entities responsible for use of chemical weapons in the Syrian civil [sic] war was the initiative by the United States that also drafted the resolution. It was adopted rather very fast--"just two days after the Russian Foreign Minister Sergey Lavrov and the US Secretary of State John Kerry reached an agreement on the drafted text in Kuala Lumpur."
So here are highlights from Security Council Resolution 2235 submitted by the US and agreed upon by Russia with all the other SC members:
1. "[the UN SC is] noting that any such use [of chlorine as a weapon[ by the Syrian Arab Republic would constitute a violation of the CWC." = note that the Syrian government is singled out as the only possible violator of the CWC.
2. The resolution is building up a feeling of the strongest outrage" while repeating only the names of the Syrian Arab Republic: "Condemning in the strongest terms any use of any toxic chemical as a weapon in the Syrian Arab Republic and noting with outrage that civilians continue to be killed and injured by toxic chemicals as weapons in the Syrian Arab Republic ..."
Note that, nowhere in the text of the Resolution, al Qaeda, jihadist forces, foreign terror groups, or involvement of Syria's neighbors are mentioned at all. As in the previous "investigations" by the Organization for the Prohibition of Chemical Weapons (referred to as the OPCW in the Resolution), the use of chemical weapons by the anti-Syrian forces/invasion forces has not been at any point entertained as a legitimate hypothesis.
3. The resolution identifies "the use of chemical weapons [as] a serious violation of international law, and stressing again that those individuals responsible for any use of chemical weapons must be held accountable." In this way, the outrage of using al Qaeda and upgrading it into full armies used as a proxy for illegal invasion of Syria is not even considered by the representatives of the "international community" in the Security Council. Russia included.
4. The resolution implies that the Syrian government stands in the eyes of those who voted for the resolution, as guilty of the war crime--of using weapons of mass destruction--chemical weapons:
"Noting the letter of the Secretary-General to the President of the Security Council of 25 February 2015 (S/2015/138), transmitting the note of the Director-General of the OPCW, discussing the decision of the OPCW Executive Council of 4 February 2015 that expressed serious concern regarding the findings of the Fact-Finding Mission (FFM) made with a high degree of confidence that chlorine has been used repeatedly and systematically as a weapon in the Syrian Arab Republic,
Noting that toxic chemicals as weapons have allegedly been used subsequent to the adoption on 6 March of Security Council resolution 2209 (2015) ...
Reiterates its condemnation in the strongest terms of any use of any toxic chemical, such as chlorine, as a weapon in the Syrian Arab Republic;
Recalls its decision that the Syrian Arab Republic shall not use, develop, produce, otherwise acquire, stockpile or retain chemical weapons, or, transfer, directly or indirectly, chemical weapons to other States or non-State actors ...
Expresses its determination to identify those responsible for these acts and reiterates that those individuals, entities, groups, or governments responsible for any use of chemicals as weapons, including chlorine or any other toxic chemical, must be held accountable, and calls on all parties in the Syrian Arab Republic to extend their full cooperation in this regard;"
5. To this effect, the Resolution keeps emphasizing "chlorine"--the favored idea of Western propaganda:
"Requests the UN Secretary-General, in coordination with the OPCW Director General, to submit to the Security Council, for its authorization, within 20 days of the adoption of this resolution, recommendations, including elements of Terms of Reference, regarding the establishment and operation of an OPCW-United Nations Joint Investigative Mechanism to identify to the greatest extent feasible individuals, entities, groups, or governments who were perpetrators, organizers, sponsors or otherwise involved in the use of chemicals as weapons, including chlorine or any other toxic chemical, in the Syrian Arab Republic where the OPCW FFM determines or has determined that a specific incident in the Syrian Arab Republic involved or likely involved the use of chemicals as weapons, including chlorine or any other toxic chemical, and expresses its intent to respond to the recommendations, including elements of Terms of Reference, within five days of receipt;"
6. The Resolution demands, with a reference to resolution 2118, "full access to all locations, individuals, and materials in the Syrian Arab Republic that the Joint Investigative Mechanism deems relevant to its investigation and where it determines there are reasonable grounds to believe access is justified based on its assessment of the facts and circumstances known to it at the time ..."
7. Finally and most ominously, the Resolution "reaffirms ... Resolution 2118 to impose measures under Chapter VII of the United Nations Charter." This coded reference refers in the UN Charter to military and nonmilitary action to "restore international peace and security" in what the UN SC or the powers that be there define as a "threat to the peace, breach of the peace, or act of aggression." See especially Articles 39, 41, and 41 of Chapter VII.
8. Thus, thanks to this resolution, both Russia and China opened a way for the US and its al-Qaeda supporting allies to change their unsanctioned war against Syria chiefly by al Qaeda proxies into a UN-sanctioned and mandated war.
The full text of the Resolution is here: https://en.wikipedia.org/wiki/United_Nations_Security_Council_Resolution_2235