"The legislation seeks $200 billion in new taxes on retirement savings to pay for favors to Wall Street, such as excluding the first 40 percent of investment income from the capital gains tax. To accomplish this goal, the Chairman effectively eliminates the main distinctions between private workplace retirement plans, such as 401(k) plans, and public and non-profit workplace plans, such as 403(b) and 457 plans, in the name of tax code simplification and increased short-term revenue. These distinctions were designed to protect traditionally lower paid workers who feel called to serve society," De Grassi said.

 Generally speaking, Americans employed by churches, schools, non-profits and state and local governments seek their jobs in spite of what they expect to be lower wages than they might otherwise earn in the private sector. We owe these folks something for their sacrifices, which benefit everyone. The tax code has long provided a quiet and potent incentive to take on these less profitable but immensely valuable careers. This bill threatens to undo retirement plan rules that may seem unnecessarily complicated to an outsider—or even the Chairman of the House Ways and Means Committee—but they do both immediate and long-term good for millions of Americans. It would be a tragedy to have to tell all these people their ability to save has been slashed to benefit a few wealthy investors.

 We hope these destructive provisions do not survive the legislative process," DeGrassi added.

The NTSA is a sister organization of the American Society of Pension Professionals & Actuaries (ASPPA), representing more than 3,000 members.

The ASPPA issued its own statement on Thursday, criticizing the proposed double taxation of retirement savings.

"Chairman Camp's tax reform proposal would subject all retirement plan contributions to the 10% surtax. The result is double taxation of these contributions — totally ignoring the fact that these contributions are just tax–deferred, not a permanent exclusion, and will be subject to ordinary income tax when they are withdrawn after retirement. Should this proposal become law, a small business owner could pay a 10% surtax on all contributions made to a qualified retirement plan today, then pay tax again at the full ordinary income tax rate when they retire.  Penalizing small business owners for contributing to a plan is going to make them think twice about sponsoring a plan at all, and their employees could lose their workplace retirement plan. Double taxation is hardly what we hoped to see in any tax reform proposal," said ASPPA CEO/Executive Director Brian Graff.

"We are also very concerned about the freeze on contribution limits until 2023. The cost of living in retirement is not going to be frozen. On top of the double taxation, this is a real blow to employer-sponsored retirement plans, and to American workers' retirement security."

And in a statement released shortly after Camp's announcement on Wednesday, President and CEO of the Insured Retirement Institute (IRI) Cathy Weatherford said, "Tax incentives for retirement savings have been a powerful tool in helping millions of Americans save and prepare for their retirement years, particularly for middle-income Americans, who would be less likely to save if these incentives were reduced or eliminated."

She continued, "As such, maintaining incentives for retirement savings will be essential to helping Americans attain financial security during their later years. We will continue to communicate the importance of these incentives to policymakers, and look forward to working with Chairman Camp to ensure that retirement savers are protected in any tax reform legislation."

Under Camp's plan, corporations would have a maximum income tax rate of 25 percent, down from 35 percent, while individuals would have a top rate of 25 percent, down from 39.6 percent.

In addition to retirement groups, however, the plan has come under fire from a wide range of critics, including manufacturers, the poor, Wall Street banks, governors and deficit hawks.