WASHINGTON—The U.S. Supreme Court sided with an employer Tuesday, ruling that the year a worker first becomes disabled determines his Longshore and Harbor Workers' Compensation Act benefit payment amount.

Benefit award calculations are not determined by the year a judge orders their payment but by the year a worker becomes disabled, the high court found in clarifying the meaning of a phrase within the act.

Under the LHWCA, benefits for most disabilities are capped at twice the national average weekly wage for the fiscal year in which an injured employee is “newly awarded compensation,” court records state.

The LHWCA is administered by the U.S. Department of Labor and provides compensation for employees killed or disabled as a result of injuries occurring on U.S. navigable waters.

In the case of Roberts vs. Sea-Land Services Inc. et al., the high court clarified the meaning of “newly awarded compensation.”

Petitioner Dana Roberts slipped on ice and injured his neck and a shoulder in 2002 while working as a gatehouse dispatcher for Sea-Land at a Dutch Harbor, Alaska, marine terminal.

Sea-Land voluntarily paid Mr. Roberts benefits until 2005.

In 2007, after Mr. Roberts filed an LHWCA claim, an administrative law judge awarded him benefits based on a 2002 maximum statutory rate amounting to $966.08 per week.

But Mr. Roberts sought reconsideration, contending that his benefit award should have been set at a higher statutory maximum rate for fiscal year 2007, when he was “newly awarded compensation” by the administrative judge.

Under the 2007 rate, he would have been entitled to $1,114.44 per week.

The administrative law judge denied Mr. Roberts' reconsideration request, and the Department of Labor upheld the judge's denial.

The 9th U.S. Circuit Court of Appeals affirmed, holding that an employee “is ‘newly awarded compensation' when he first becomes entitled to compensation,” or when he becomes disabled.

On Tuesday, the Supreme Court affirmed the 9th Circuit's finding.

Among other reasons, the high court said that determining benefit amounts based on the year a worker first becomes disabled avoids disparate treatment of similarly situated employees.

“Roberts’ reading would permit two employees who earn the same salary and suffer the same injury on the same day to receive different maximum compensation rates based on the happenstance of their obtaining orders in different fiscal years,” the Supreme Court said.

Additionally, “Roberts’ rule would reward employees who receive voluntary payments with windfalls for initiating unnecessary administrative proceedings to secure a higher rate, while simultaneously punishing employers who have complied fully with their statutory obligations,” the court said.

But Justice Ruth Bader Ginsburg dissented in part.

Justice Ginsburg said it is not reasonable that “newly awarded compensation” means in the year a claimant becomes “statutorily entitled to compensation,” or the year they become disabled.

“I would reverse the 9th Circuit’s judgment and hold that an employee is ‘newly awarded compensation’ when her employer either voluntarily agrees to pay compensation to her or is officially ordered to do so,” Justice Ginsburg wrote.