It's a gas, gas, gas!

Men walk away from a cloud of tear gas during a protest Monday, Aug. 18, 2014, for Michael Brown, who was killed by a police officer Aug. 9 in Ferguson, Mo. Brown's shooting has sparked more than a week of protests, riots and looting in the St. Louis suburb. (AP Photo/Charlie Riedel)

Remember "gassing his own people"? That's what George W. Bush said about Saddam Hussein, and it was part of his case for invading Iraq. But of course, there's gas and then there's gas: Even as a weapon, some gases are worse than others. What about tear gas, which the police in Ferguson, Mo., seem to be using (no pun intended) liberally? Is all tear gas the same? And when is it safe to use against protesters...or those breaking the law?

Philadelphia-based freelance journalist Joanne Stocker, along with Robin Jacks, are here to raise some very uncomfortable questions:

Social media reporting during the Arab Spring brought new evidence of expired tear gas sales, drawing criticism from human rights organizations. Amnesty International, in particular, criticized the United States for selling military leftovers to oppressive governments such as Egypt's and Bahrain's. Tear gas has not been used this wantonly in an American city in modern times; even its deployment against WTO protesters in 1999 and Occupy Oakland in 2011 was isolated and largely away from residential areas. Chemical munitions deployed in residential areas can be deadly: Physicians for Human Rights, an independent organization, recorded 34 tear gas related deaths in Bahrain from 2011 to 2012, many from inhalation in close or confined spaces.

The chemical weapons convention prohibits the use of chemical munitions in war; the weapons sales angered activists and rights groups who saw it is as evidence of American companies profiting from attacks on protesters. An exception to the chemical weapons convention, to which the United States is a signatory, is the use of chemical munitions for domestic law enforcement purposes; it is under this allowance that tear gas and other chemicals are now deployed in Ferguson.

Stocker and Jacks show the evidence that -- as the protests in Missouri drag on into their 11th night -- the cops are also dipping into tear gas munition stocks that date back to the Cold War, raising questions about dangers from gas that has expired and may be more harmful than more current variations of the chemical agent. That's a great question, but more troubling is that we are so accepting that this is a good tool for police agencies. Clearly, when tear gas is deployed badly, it can even kill.

Stephen Hawkins, U.S. head of Amnesty Int'l--which sent ten observers but kept far from scene to witness--on MSNBC hits "de facto" curfew with police forcing people out.  Saw tear gas and smoke bombs lobbed into crowds without knowing if kids or elderly there, which "violate international" human rights norms.

At lot of "norms" have been violated this week. This is just one thing we should re-consider -- if and when the smoke clears in Ferguson.