How do you get the likes of Sen. Bill Nelson and Rep. Steve Southerland on the same side of an issue? Threaten to touch Florida’s share of money from the BP oil spill settlement.

After months of political wrangling, Congress in June finally passed the RESTORE Act (which President Obama signed into law in July). It allocates 80 percent of Clean Water Act fines from the 2010 Deepwater Horizon oil spill to Florida and the four other Gulf states. The act directs that the fines returned to those states be used for ecological and economic recovery efforts.

Florida law ensures that the Panhandle counties most affected by the spill — Escambia, Santa Rosa, Okaloosa, Walton, Bay, Gulf, Franklin and Wakulla — receive three-fourths of the Sunshine State’s share of the money. According to the funding formula, that could mean tens of millions of dollars for each county.

Until recently, the biggest concern was how local communities would decide how to spend the money. For example, Apalachicola recently crafted a resolution that requests that municipalities have more control over the dollars, leaving counties the power to spend the remainder only in unincorporated areas.

But that’s a minor dustup compared to what’s brewing in Washington.

Last week, reports swirled that the Justice Department was negotiating a deal with BP to settle civil and criminal charges resulting from the oil spill. It would give the federal government more control over the billions of dollars in fines paid by BP, shifting that authority away from the affected states, and it would divert a greater portion of those fines toward a Natural Resource Damage Assessment (NRDA), reducing the civil penalties for violating the Clean Water Act. NRDA fines have stricter federal controls on them, whereas CWA fines are subject to the RESTORE Act and are more flexible.

The NRDA fines are also tax deductible. That means BP would be able write off hundreds of millions of dollars in penalties, thus easing the financial pain it should feel for operating in such a reckless and destructive manner.

Put simply, that deal would be outrageous. It’s a slap in the face to every resident of the Gulf Coast — and a slap on the wrist to BP.

Gulf Coast members of the House and Senate, including Florida’s 2nd District Rep. Southerland, R-Panama City, and 1st District Rep. Jeff Miller-R-Chumuckla, recently sent a letter to Attorney General Eric Holder expressing “in the strongest possible terms” their opposition to any settlement agreement that disproportionately applies penalties to NRDA over the CWA.

“Any attempt to do so would be viewed as an effort to circumvent the will of Congress and the president, and the enacted formulas and procedure agreed upon in public law under the RESTORE Act,” the letter says.

Sen. Nelson, a Democrat, wrote to President Obama: “I urge you to hold BP fully accountable for the harm it caused and send the bulk of the fines to the Gulf as directed by the RESTORE Act. Anything less would be an injustice to Gulf Coast communities.”

The RESTORE Act rightly allocates the majority of oil spill money to the areas that were affected by the environmental and economic disaster, and it places responsibility for spending those funds in the hands of state and local officials who can be held accountable for it. Holder’s move not only would undermine all that, it would essentially reward BP for its role in fouling the Gulf Coast and crippling its tourism and seafood industries.

What’s especially startling about this development is the timing. Why now? Why did President Obama sign the RESTORE Act only to have his Justice Department undo most of it?

The Gulf Coast thought it had finally cleaned up this mess. Now here comes Washington muddying the waters. Holder needs to back off and let the RESTORE Act work.