"What is the history of having lobbyists? What would it take to get rid of them?" --  Marcia Friedman, Southern California

Lobbyists have a deep-rooted history in our country and are protected by the Constitution. For better or worse, they aren't going anywhere.

Although it's well known that the First Amendment guarantees freedom of religion and of the press, it's often forgotten that it also guarantees the right to "petition the government for a redress of grievances." That includes such things as signing petitions, filing lawsuits, and, yes, lobbying.

The word "lobbying" dates back to the early 19th century and likely referred to the lobbies of hotels or legislative buildings where petitioners would make their case. (The urban legend that it specifically came from the Willard Hotel in Washington during the Grant administration has been debunked.)

Today, lobbying is a billion-dollar industry. According to the Center for Responsive Politics, $3.47 billion was spent on lobbying in 2009, when 13,741 registered lobbyists were active.

Business interests such as health care were among the top sectors, spending more than $500 million apiece on lobbying that year. Although further down the list, ideologically driven groups spent another $153 million.

Lobbyists also work for less controversial clients such as nonprofits, universities and churches.

Over the years, Congress has regulated lobbying to curb its influence with varying degrees of success. In 1946, Congress passed the Federal Regulation of Lobbying Act, which required lobbyists to register with the Clerk of the House of Representatives and the Secretary of the Senate.

In a 1954 case, the Supreme Court narrowed  the definition of lobbying. Over the years, lobbyists found other loopholes to avoid filing disclosure forms, some of which were closed by the Lobbying Disclosure Act of 1995.

In his Jan. 27 State of the Union, President Obama called for a requirement for lobbyists to disclose each contact they make with a federal official and strict limits on contributions that lobbyists give to candidates.

-- Leah Carliner, Congress.org