MOBILE — Alabama’s top prosecutor on Thursday urged the U.S. Supreme Court not to block next week’s scheduled execution of 61-year-old Phillip Hallford to allow a lower court hearing on lethal injection.

Attorney General Troy King told the high court in a filing that Alabama’s lethal injection protocol meets the standard already approved by the justices when they upheld its use in Kentucky, even though Alabama’s protocol has never had a final court test.

King’s filing came in response to Hallford’s bid to block his March 19 execution until the 11th U.S. Circuit Court of Appeals holds a March 31 hearing in Atlanta on Hallford’s lethal injection challenge.

The 11th Circuit last month granted a stay of execution, without explanation, and King has asked the Supreme Court court to lift it.

Hallford was convicted in Dale County for the 1986 shooting death of his 15-year-old daughter’s boyfriend, 16-year-old Charles Eddie Shannon. He has been on death row at Holman Prison for about 22 years.

Philadelphia attorney Andrew E. Kantra, who represents Hallford in the lethal injection challenge, said while the procedures in Alabama may be “substantially similar” to Kentucky’s, no court has issued a final decision on the procedures and the 11th Circuit needs time to rule on it “to fulfill its constitutional review authority.”

King’s Supreme Court filing, prepared by his capital litigation chief, Assistant Attorney General Clay Crenshaw, said Alabama has used lethal injection 16 times since changing its method of execution in 2002 from the electric chair.

And while the prosecutors acknowledge that no federal or state court has issued a final decision on Alabama’s lethal injection procedures, they said that’s because no condemned inmate, including Hallford, has filed a timely challenge to give courts time to rule on the merits.

Regardless, Hallford’s challenge, filed in June 2007, is blocked by the Supreme Court’s Kentucky decision that covered states with lethal injection protocols “substantially similar” to Kentucky’s, the prosecutors argued.

However, in his Supreme Court filing, Kantra noted that the legal argument over lethal injection protocol is still going on in several states, including Alabama.

“Alabama’s motion is no more than an attempt to execute Hallford before his appeal can be heard, rendering it eternally moot,” Kantra wrote in his request for the Supreme Court to uphold the stay of execution.

Hallford’s execution is one of six scheduled in Alabama this year — one in each of the first six months in a state that had no executions last year. Two have been carried out.