Why is Iraq's decision to expel US troops non-binding?

Question

In response to the United States' killing of an important Iranian military commander on Iraqi soil on 3 January 2020, the Iraqi parliament voted to expel US troops from the country. According to various news sources (such as Al Jazeera), this decision is non-binding as it took the form of a parliamentary resolution rather than a legislative act.

Why did the Iraqi parliament choose to respond using what looks like a consultative or advisory proclamation rather than a binding decision with the force of law? Is this because they wanted to issue a forceful-sounding message of displeasure without actually wishing the US military to leave? Or is it because the procedure for passing binding legislation rather than a parliamentary resolution is much more difficult and perhaps less likely to be successful? (For example, are there more stringent quorum or majority-voting requirements for legislation?) If the latter, are Iraqi legislators now preparing or debating legislation that will formally effect the expulsion?

Answer 1

I'm not sure there is a clear answer to this. US forces currently in Iraq aren't there as part of a formal agreement of any sort. They are there 'informally' at the invitation of the Iraqi government. Most commentators suggest that the Iraqi parliament has no capability to legally demand the removal of US troops - it would require the government to make the demand, and the parliament has no real route to force the government to make that demand.

If that sounds slightly screwy, it's because it is. Deliberately so. The system is designed to put all the meaningful power in the hands of the president and the executive. The legislative branch - the parliament - mostly gets to elect the new president, remove a president from office, and confirm the actions of the executive. Like many constitutions in the region, it isn't designed to give democratic accountability, but rather to give ethnic and factional stability, with a veneer of democratic institutions where they aren't too inconvenient. (And in Iraq's case in 2005, arguably a stable government that can effectively do the US's bidding without being overruled by popular opinion).

So as I understand it, for the Iraqi parliament to force compel the removal of US troops from Iraq, it has to force the government to take that action, which it can do by the threat of removing the president from office, or actually removing him from office and electing a new president who will do what they want. Which is probably a bigger step than they are willing to take at the moment.

Answer 2

Indeed, what we do know is what we don't know

“The current U.S. military presence is based [on] an exchange of letters at the executive level,” said Ramzy Mardini, an Iraq scholar at the U.S. Institute of Peace.

The terms outlined in those letters have not been made public.

Interestingly enough, an exchange of letters has the force of a international treaty, in some contexts.

But it appears that the resolution was passed to give backing to an eventual decision of Mahdi because technically he resigned his post already and is only acting PM at the moment:

Among legal experts, Sunday’s parliamentary vote was interpreted as advisory but crucial, providing political cover for a prime minister who has been operating in a caretaker capacity since mass protests forced him to resign in November. It was, Jiyad said, “to make sure that this decision is not legally challenged” and to demonstrate which way political winds are blowing.

“There is no law required to kick the U.S. military out because a law did not establish their presence,” Mardini said. “Baghdad has demonstrated its signal to Washington that the presence of the U.S. military is no longer wanted in Iraq. Since parliament is responsible for determining who is the next prime minister, it’s hard to imagine that individual going against the parliament’s vote.”