The mayor, who is running for state Assembly, explained his position in a Monday interview.
"I was trying to get my questions answered that night and didn't seem to get an answer," he said.
He said he had grown frustrated with the disagreement and did not participate in the vote so that things could calm down among council members.
The California Youth Soccer League, a nonprofit with a Costa Mesa chapter, requested that the city waive the fee, valued at about $28,000 a year, for two fields to allow kids on the Westside to play on their turf.
The group met the requirements to qualify for a fee waiver. It's one of eight groups categorized as a Group 1 user, which qualify for a fee waiver because they are nonprofit, they don't turn anyone away and have at least 75 participants from Costa Mesa.
The fee waiver for the soccer league was recommended by the city's Parks and Recreation Commission.
When it came time to vote on whether the group could have their fees waived, every council member but Mansoor cast a vote.
The vote was 2-2, and the motion to waive the fee failed.
When Foley asked Mansoor if he had voted, he replied that he didn't. When Foley told him he had to vote, Mansoor said he didn't.
Costa Mesa City Atty. Kimberly Hall Barlow then asked to convene a closed session.
When the council emerged from the session, Mansoor was absent.
This time, Councilman Gary Monahan, who voted against the fee waiver before the closed session, motioned for approval of the fee waiver, allowing it to pass 3-1. Councilman Eric Bever dissented.
Mansoor said in hindsight that he could have motioned for the issue to be continued until city staff answered his questions.