Investment brokers and advisers are blocking the passage of federal rules that would require them to put their clients' interests first when handling retirement accounts.

The U.S. Department of Labor, which oversees retirement plans, recently announced it was delaying the release of the rule change from August until January. Even that deadline could be missed, according to officials at Employee Benefits Security Administration.

Under current rules, brokers and advisers must believe only that an investment is "suitable" for a client, including that person's income, age and financial goals, at the time they recommend it.

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But just because an investment is suitable doesn't mean it's sound, critics have long complained. Nor does that standard stop financial professionals from charging excessively high fees for their services. One reason that's a problem: Brokers often get a commission based on how many dollars flow into a given investment. Brokers and advisers also aren't required to disclose any financial incentives they might have to push particular products, even though they are paid by securities firms to do just that. For example, individual retirement accounts often charge higher fees than 401(k) plans, giving brokers an incentive to promote rollovers.

Instead, consumer advocates favor requiring brokers and advisers to adhere to what is known as the "fiduciary standard." That requires investment brokers and advisers not only to offer people the best possible advice, taking into account their financial needs, but also to put firms' own financial interests behind those of clients. Fees are also typically based on how much money a firm has under advisement, while brokers are prohibited from making trades aimed at boosting commissions.

The securities industry has long opposed subjecting investment brokers and advisers to the stricter fiduciary standard. As a result, industry groups such as the Securities Industry and Financial Markets Association and Financial Services Roundtable, along with companies such as Morgan Stanley and Fidelity Investments, are pushing to block or weaken the proposed rules.

"SIFMA believes the Department of Labor proposal is an overbroad expansion of the fiduciary standard that will undermine efforts by employers and service providers to educate workers on the importance of responsible retirement planning. SIFMA is concerned that this proposal will limit investment choices and drive up costs for the individuals it is intended to protect," the group said in a statement.

Not everyone in financial services takes that position, it's worth noting. A number of individual financial advisers and smaller firms strongly object to efforts to halt the rule change. Among the groups supporting the proposed rule changes is the CFA Institute, which awards the prestigious Chartered Financial Analyst designation.

Elliot Weissbluth, founder and CEO of wealth management firm HighTower Advisors, says it is "obvious" why major broker-dealer firms are fighting a shift to the fiduciary standard.

"It's going to hurt their ability to sell product," he said. "It's pretty obvious -- when your current obligations are to generate profits for yourself and now you have to switch and put the clients' interests ahead of your own, that is a threat to your business model."

Weissbluth dismisses SIFMA's contention that the debate comes down to consumer choice. Rather, the main issue is whether the consumer or the broker is legally responsible for knowing all the possible risks involved in a given investment.

"Obviously, anyone who is legitimately concerned with the clients' interests shouldn't have any problem with [the rule change]," Weissbluth said. "So if you have a problem with it, that says your interests are ahead of the clients. Otherwise, what's the problem with it?"

The Government Accountability Office has previously warned about how investment firms conflicts of interest can lead to higher costs for investors. Investigators found that some organizations offering advice about Individual Retirement Accounts receive payments from mutual funds to steer clients to the funds' products.

This activity, called "revenue sharing," is legal and the consumers are never told of it. This can be done overtly or simply by highlighting one firm's products as examples of investment options under each asset class, under the guise of investor education.

"Plan participants often receive guidance and marketing favoring IRAs when seeking assistance regarding what to do with their 401(k) plan savings when they separate from their employers," GAO found in a 2011 report. "GAO found that service providers' call center representatives encouraged rolling 401(k) plan savings into an IRA even with only minimal knowledge of a caller's financial situation."

This type of behavior is inevitable given the current rules, said Scott Holsopple, managing director of retirement solutions with The Mutual Fund Store.

"I'm a big believer that people generally do what they're incented to do," he said. "So you have to ask yourself, if you're working with someone that is paid to sell a product, whether they are doing something that is going to make them the most money or something that is in the best interest of you or your retirement goals."

Holsopple believes you only need to know two things to protect yourself in this situation. The first is how is the person you're working with going to get paid. "If they're getting paid a percentage of the product based on the sale of the product, you have to wonder if they're acting in your best interests," he said.

The second, and more obvious, rule of thumb: Don't invest in anything you don't understand.

"You have to know what you're invested in," Holsopple said. "We're big believers that unless you have significant assets, say, several million dollars, you should be in publicly traded investments. I've seen a lot of cases where people are put into non-traded real estate investment trusts. While they come with big commissions, they're very hard to get out of, and you don't necessarily have a view into what they're value is on a day-in, day-out basis."

The stakes in this fight are particularly high right -- not just for individuals but for the nation as a whole -- because the U.S. is in the middle of retirement rollover boom. In the past decade, the amount of money shifted by former employees from 401(k)-style plans to IRAs has increased 60 percent. According to Cerulli Associates, a Boston-based consulting and research firm, IRAs now hold $6.5 trillion, half a trillion dollars more than is in 401(k)-style accounts. In 2012 alone $321 billion was shifted into IRAs.