"CBO is not required to show their work, like we were required at school, when announcing economic impact results."
Republicans have increasingly complained about the way CBO scores bills, and while Murphy said the point of the bill is not to point out CBO errors, he said studies have shown that CBO has made dramatic errors in the past.
"Massive spending bills — like the President's trillion-dollar healthcare program — can be misrepresented, allowing political spin to frame budget-busting bills as ones that will save taxpayers money," Murphy said earlier in the week. On Thursday, he also indicated skepticism about other CBO claims.
"When the CBO says the stimulus saved 3.3 million jobs, or tax rates don't impact decisions by individuals or businesses, or that cutting spending will slow economic growth, we currently have no way of understanding their conclusions," he said.
The bill, H.R. 6136, is supported by Americans for Tax Reform President Grover Norquist.
"Congressman Tim Murphy's CBO Transparency Act is step one in reforming Washington’s broken budget process," Norquist said this week. "It will be the model for similar reforms throughout the federal government and all 50 states."
Murphy said forcing CBO to "show its work" would enhance the credibility of CBO, because others could examine its methods and help improve its conclusions.
"Like any scientific study, opening up the details of CBO analysis for greater inspection and peer review will enable us to better understand how decisions are made," he said. "Once the information is out there and can be reviewed by Congress and all Americans, is the information correct? Did they consider all the facts? Was something left out? Was their analysis done right?"
The bill is sponsored by Reps. Paul BrounPaul BrounCalifornia lawmaker's chief of staff resigns after indictment Republican candidates run against ghost of John Boehner The Trail 2016: Let’s have another debate! MORE (R-Ga.), Patrick Tiberi (R-Ohio), Steve Stivers (R-Ohio), Louie GohmertLouie GohmertCongress must not pass Endangered Species reform bill Gohmert calls Yates 'a political hack' Dem Castro weighs challenge to Cruz MORE (R-Texas) and Dennis Ross (R-Fla.), and one Democrat, Rep. Gene GreenGene GreenLawmakers worry ObamaCare fight could suck air from other priorities Midwest Dems feel left out in cold Overnight Healthcare: Hospitals plot attack against ObamaCare repeal MORE (Texas).