Republicans launched a systematic attack on the official scorekeepers of their tax bill

The day before Senate Republicans voted to pass their tax bill, they were faced with an expert analysis of their proposal that undercuts all of the major GOP selling points.

Faced with the choice of taking their tax bill back to the drawing board, or doubling down, Republican leaders made a concerted effort to undercut the official analysis of their bill, circulating two pages of “response points,” giving senators an arsenal of excuses to talk around the unfavorable projections, according to the New York Times, which acquired the documents.

The evaluation from the Congress’s Joint Committee on Taxation, the official body tasked with estimating the tax bill’s impact, should have been enough to end the Republican “fantasy of magical growth” in the economy, the Finance Committee’s top Democrat, Sen. Ron Wyden (OR), said. The JCT reported that the Senate Republican’s tax bill would grow the economy by about 0.8 percent over 10 years, and still cost about $1 trillion.

But the memo said “the substance, timing and growth assumptions of JCT’s ‘dynamic’ score are suspect,” and told senators to point out the “consistently” wrong analysis models. They advised going after the Congressional Budget Office, which also analyzes the impact of legislation.

Senate Republicans’ talking points reflected the memos doled out by leadership.

“I think it’s pretty clear they’re wrong,” Majority Whip Sen. John Cornyn (R-TX) said of the JCT score after its release.

Almost immediately after the JCT’s analysis was made public, the Republican-led Senate Finance Committee released a statement saying the score couldn’t possibly be right because the bill wasn’t in its final form.

“An analysis of tax provisions that do not reflect the final outcome of the evolving Senate tax bill — which will be amended on the floor this week — is incomplete,” the committee’s spokesperson, Julia Lawless, said, adding that “the findings of JCT are curious and deserve further scrutiny.”

While it’s true that Republicans were still debating key parts of the bill in the final hours before the vote, the committee analyzed what Republicans approved in two Senate committees, and largely had the support of the majority of the Senate Republicans’ conference.

But Republicans have become accustomed to questioning the official analyses of their signature pieces of legislation. At the start of the year, when the GOP was trying to repeal Obamacare, they repeatedly balked at the Congressional Budget Office’s scores of the Republicans health care bills, all of which projected millions of uninsured Americans.

Cornyn echoed similar talking points from the health care debate, saying he didn’t trust the JCT’s model for analysis:

“One thing you know is that they are always going to be wrong, but you don’t know if they are going to be too high or too low,” he said. “But even their models, I don’t think, take into account the enormous influx of investment back into the United States and positive impact that will have on economic growth.”

Sen. James Lankford (R-OK), a deficit hawk who early on expressed concern about the tax bill’s impact on the deficit, also questioned the “assumptions” made in the analysis.

“I’m amazed that they would think that our growth is less than 1 percent in 10 years; that’s a little surprising,” Lankford said, referring to the JCT’s estimate of the tax bill’s growth effect. “I have not seen anything that low as a growth estimate, so I’m trying to go through and figure out their assumptions.”

Others were much bolder in their dismissals.

Sen. John Barrasso (R-WY), who first said he had not seen the JCT score, later seemed to recall it as something he didn’t need to pay attention to.

“Oh, that’s the one that doesn’t believe that there’s going to be economic growth? Yeah, I ignore that,” Barrasso said.

The analysis showed a wildly lower growth number than what Republicans have been promising; Treasury Secretary Steve Mnuchin had said, “Not only will this tax plan pay for itself, but it will pay down debt.” As Republicans hurtle toward passing the bill, the report massively undermines the GOP’s argument for the plan.

Sam Greenberg, an analyst with the right-leaning Tax Foundation, calculated an annual 4 percent year-over-year GDP growth, which Trump has suggested would mean the economy was about 12.9 percent larger on average. The JCT score, which calculates economic growth over a decade, estimated the tax bill would grow the economy an average of 0.8 percent in that time.

This is the first dynamic score of the tax bill, meaning it forecasts how the economy will react to the policy. Republicans are making the argument that huge corporate tax cuts will bring back jobs and investments and massively grow the economy — in other words, that tax cuts would pay for themselves. They have long called for this kind of scoring.

But now, with an estimate much less optimistic than what they’ve been selling to their constituents, they ignored the numbers and went with intuition, passing the proposal the following day.

“It’s just a reference point — it’s not going to influence my decision on the bill,” Sen. Thom Tillis (R-NC) said of the score before the vote.