The US Senate has approved a bill seeking to ban insider trading by members of Congress.
Under current rules, lawmakers can trade stock unrestricted even though they may have specialist knowledge.
The bill, passed by a bipartisan 96-3 vote, would require them to file disclosures of trades within 30 days.
Congress is suffering from historically low approval ratings, prompting frank admissions that the bill is aimed at cleaning up its public image.
"When polls show low public confidence in Congress, there is a strong desire to address the concerns that underpin the public's scepticism," Maine Republican Susan Collins said.
The bill is also expected to pass the House of Representatives, where Majority Leader Eric Cantor said he would introduce the legislation next week.