TALLAHASSEE, Fla. -

A former South Florida police officer convicted of killing nine people is asking the U.S. Supreme Court to block his execution scheduled for Tuesday.

Lawyers for Manuel Pardo Jr. filed an appeal and requested of a stay of execution on Friday.

They're arguing that state courts failed to provide a meaningful review of his challenge to changes in Florida's three-drug lethal injection cocktail. They also contend psychiatric and competency information about Pardo was never forwarded to the state Executive Clemency Board.

The state filed a response arguing that Pardo's constitutional rights were not violated.

The 56-year-old ex-Sweetwater officer admitted he killed the victims in 1986. He testified at his trial that they were drug dealers who "have no right to live."