I just searched for more than 15 minutes trying to find the Senate votes on the Iran deal. It was a very complicated piece of nastiness with more than one vote (voting for cloture/and various aspects that are tangled and confusing) and I could find nothing at all that indicated Sessions voted for it. I did find the below, and other indications that he was opposed. Could you post your source that Sessions voted for it?
https://www.al.com/news/2015/09/sessions_on_iran_deal_i_think.html
Sessions on Iran deal: ‘I think it’s a mistake’
Posted Sep 17, 2015
In indicating his disapproval for the pending nuclear agreement between the United States, Iran and four other countries, U.S. Sen. Jeff Sessions, R-Ala., called for a broader strategy to confront Islamic extremism in the Middle East during a speech Wednesday from the Senate floor.
“I think it’s a mistake. I’m going to vote ‘no,’” Sessions said of the agreement, saying that if such a deal is consummated, “it will create instability even more so in the Middle East and can alarmingly lead to the proliferation of nuclear weapons in multiple nations in the Middle East.”
Sessions became a co-sponsor of the Corker bill on 04/15/2015.
The Corker bill put the onus on Congress to muster 67 votes to block the Iran agreement.
The final vote was 98-1 passing Corker’s bill. The bill was sent to house where it passed.
The only Senator to vote no was Tom Cotton. I don’t know which senator was missing from the vote.
decent explanation of Corker’s chicanery.
https://thehill.com/blogs/floor-action/senate/241355-senate-votes-to-approve-Iran-review-bill
Take a look at how he voted on the legislation that said that Obama could negotiate a deal with Iran, and it would be valid if 50 percent of the Senate voted for it, instead of the 2/3 necessary for a treaty. That was a Corker deal. I believe that shows he was very dirty. I never believed that a majority vote can take away the right of 1/3 of the Senate to block a treaty, but it was never challenged.