TALLAHASSEE -- Gov. Rick Scott signed a bill into law Friday aimed at accelerating the pace of the death penalty process in Florida that could make the governor the most active executioner in modern state history.

The measure, dubbed “the Timely Justice Act” by its proponents, requires governors to sign death warrants 30 days after the Florida Supreme Court certifies that an inmate has exhausted his legal appeals and his clemency review. Once a death warrant is signed, the new law requires the state to execute the defendant within six months.

In a lengthy letter accompanying his signature, Scott aggressively countered allegations by opponents that the law will “fast track” death penalty cases and emphasized that it “discourages stalling tactics” of defense attorneys and ensures that the convicted “do not languish on death row for decades.”

The bill, which passed the House 84-34 and was approved by the Senate 28-10, allows the governor to control the execution schedule slightly because it requires him to sign a death warrant after the required clemency review is completed and only the governor may order the clemency investigation. Scott’s office told lawmakers that because at least 13 of the 404 inmates on Death Row have exhausted their appeals, his office has already started the clock on the clemency review.

If Scott were to sign death warrants for the 13 eligible inmates, and their executions were to continue as planned, he will be on schedule to put to death 21 murderers since he took office in January 2011. The only other recent governor who executed that many people was former Gov. Jeb Bush, who ordered the execution of 21 convicted killers but did it over an eight-year period.

The only governor to commute a death sentence since the state passed its current capital punishment law in 1973 was former Gov. Bob Graham who reduced the sentences of seven men between 1979 and 1983 for various reasons, according to the Death Penalty Information Center.

The clemency provision was added at the request of Scott’s general counsel, Pete Antonacci. The clemency investigation allows for the state Parole Commission to conduct an off-the-record review of the entire case and recommend whether the death warrant should be signed or the sentence commuted.

Opponents warn that the accelerated clock will diminish the opportunity to exonerate anyone on Death Row who has been wrongly convicted, reduce the opportunity to challenge convictions because of ineffective counsel, and produce a “bloodbath” of executions in the next month.

“Gov. Scott came to Tallahassee to restructure our economy and drag us out of the recession, but if this happens history will note him as the governor who signed more warrants than anyone else,’’ said Howard Simon, executive director of the American Civil Liberties Union of Florida.

But Antonacci, who has overseen the governor’s death penalty review, disagrees. The clemency provision was added at his request and that clemency investigations typically take from four months to a year, after which the governor and Cabinet serving as the clemency board must decides whether to commute a sentence or move forward with the death warrant. But, he acknowledged, the 13 inmates now undergoing the review “will be done within the next year.’’