The House ethics committee voted Wednesday to establish an investigative subcommittee into allegations involving ex-Rep. Eric Massa (D-N.Y.), acknowledging the possibility that Members or House aides may have failed to report the accusations.

“The allegations surrounding former Representative Massa are serious and warrant a full and complete investigation,” Chairwoman Zoe Lofgren (D-Calif.) and ranking member Jo Bonner (R-Ala.) said in a joint statement.

Lofgren and Bonner will chair the subcommittee. Reps. Ben Chandler (D-Ky.) and Mike Conaway (R-Texas) will also serve on the panel.

The House ethics committee had announced an inquiry focused on Massa’s office in March but had not established an investigative subcommittee.

“Pursuant to Committee Rule 18(a) the Chair and Ranking Republican Member of the Standards Committee have been jointly engaged in an investigation concerning alleged or actual misconduct on the part of former Representative Massa including actions that were offensive, inappropriate, created a hostile work environment, or were otherwise in violation of laws, rules, regulations or other standards of conduct,” states the committee’s resolution creating the subcommittee.

The investigation will also review whether Members, House officers or aides may have had “personal knowledge, or were or may have been made aware by or through [other] persons, of such alleged or actual conduct on the part of former Representative Eric Massa that was in violation of laws, rules, regulations or other standards of conduct,” and whether those individuals properly reported or disclosed those allegations.

Republican lawmakers have repeatedly pushed for an investigative subcommittee to focus on what Democratic leaders knew about Massa’s behavior and how they responded. The House most recently referred a resolution that would create a subcommittee to the ethics panel earlier this month.

“The American people have the right to expect their elected leaders to adhere to the highest possible standards of ethical conduct,” Minority Leader John Boehner (R-Ohio) said in a statement. “Members of Congress, especially Leaders, have clear responsibilities when it comes to protecting Congressional employees and interns from harassment and abuse. I hope this investigation will establish, in a timely fashion, whether the Democratic leadership lived up to those standards in the case involving Congressman Massa and his employees.”

Massa, who resigned from the House in March in the face of accusations that he had sexually harassed his own aides, denied any wrongdoing during several television and radio interviews in March but admitted to using “salty language” and engaging in improper physical contact with his staff.

Attorneys for two former Massa aides, including chief of staff Joe Racalto, acknowledged last week that the aides filed complaints with the Office of Compliance in late March regarding the allegations.