JEFFERSON CITY, Mo. -- The duration of jobless benefits for thousands of unemployed workers could turn on how the state Supreme Court interprets a sentence in the Missouri Constitution regarding vetoed bills.

The court heard arguments Wednesday on whether the Senate exceeded its powers when it voted in September to override Gov. Jay Nixon's veto of a bill effectively cutting unemployment benefits from 20 weeks to 13 weeks. The quickened clock began ticking Jan. 1 for people filing new claims.

Missouri's jobless benefits are now the second shortest nationally, after North Carolina's 12 weeks.

"If the statute is upheld, that's limiting real people's families, real people's livelihoods, on a week-to-week basis," James Faul, an attorney representing unemployed workers challenging the law, said after Wednesday's court hearing.

There was no mention of the potential benefit cuts during the half hour of legal arguments. Instead, lawyers and judges focused on whether the timing of the Senate's vote complied with the state constitution.

At issue is a provision summoning the Legislature back for a September session to reconsider bills that are vetoed either after their regular session ends in May or within the final five days of that session.

The unemployment bill was vetoed before the last week of the 2015 session, and the Republican-led House quickly voted in May to override the Democratic governor's veto.

But the Republican-led Senate waited to complete the veto override during September session, which was triggered because Nixon vetoed other unrelated bills.

The attorney general's office defended the Senate's action, arguing Wednesday lawmakers are free to consider any vetoed bills during the September session -- even those struck down before the final week of the regular session. That echoed a November ruling by Cole County Circuit Judge Jon Beetem, who said the constitution allows "bills" -- plural -- to be considered during the September session without limiting that to only those vetoed after a certain date.

"The plain language is clear" in the constitution, deputy state solicitor general Jeremiah Morgan told the Supreme Court.

Faul asserted the constitutional provision is ambiguous. He said a strict analysis of singular and plural words should "not prevail over the constitution's spirit" of setting timelines and procedures for the Legislature to follow. Taken to an extreme, he said a literal interpretation could allow lawmakers in September 2016 to consider overriding bills vetoed by Nixon in his first year in office in 2009.

Morgan denied that but conceded a literal reading could allow a bill vetoed in early 2015 to be taken up for an override in September 2016, because it would still be within the two-year term of the Legislature. That has not been the recent practice of the Legislature, which considers overrides only during the year in which the veto occurred.

Supreme Court judges cast skepticism on both attorneys' arguments. For example, Judge Paul Wilson questioned Morgan's assertion one chamber could vote on an override during a separate session than the other chamber. And Chief Justice Patricia Breckenridge repeatedly pressed Faul for a better explanation of why he thought lawmakers couldn't consider all vetoed bills during their September session.

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