Does procurement report in to supply chain or legal at your org? Share why you think this reporting structure works (or doesn't) in the comments.

The legal T's & C's of the vendor contract is only one piece of procurement body of work.  The performance management of the vendor, the relationship management of the vendor, and the market analysis & response to the market reviews are much larger pieces of procurement than the contract itself.  Unless vendors are constantly deviating from the contract verbiage & you need to hold vendors accountable to the document constantly, the business (supply chain team) is who has the most skin in the game with procurement and should own. 

It is simply part of the total supply chain. I've had companies I worked for where they were separate and never worked well. Having them under legal or anything else is beyond me as a professional as such an anchoring doesn't allow sourcing/procurement to deliver the best they can.