Registered lobbyists, they said, may not be considered friends. The undercover operative in the sting case, Tyron B. Ali, was a Philadelphia lobbyist.
Steve Miskin, spokesman for House Republicans, who hold the majority in the chamber, said party leaders saw the ban as a quick way to stop a questionable practice. Under current ethics rules, legislators may accept gifts - including cash - as long as they report them on their annual financial-disclosure forms.
"A lot of members in the House were frankly surprised that cash donations were even legal," Miskin said Wednesday. "The ban was something that we could do immediately to change that."
Under the measure, imposed by a rule change, a member who violates the ban would be referred to the House Committee on Ethics, which could launch its own inquiry into matter and recommend censure or expulsion.
The ban only applies to the House, although several lawmakers in both chambers have said they will introduce broader legislation banning not just cash gifts but money orders, gift cards, and prepaid credit cards.
The Senate could move such a bill as early as next week, said Erik Arneson, spokesman for Senate Majority Leader Dominic Pileggi (R., Delaware).
The sting investigation, first reported March 16, began in 2010 under Republican Tom Corbett, then the state's attorney general and now its governor.
After Attorney General Kathleen G. Kane took office last year, she shut it down. She said she did so because she believed the investigation was poorly managed and possibly tainted by racial profiling.
The state prosecutors who led the sting have countered that it was a by-the-book investigation that had caught several elected officials taking cash and had the potential to capture more.
Barry Kauffman, executive director of Common Cause of Pennsylvania, on Wednesday called the House leaders' cash gift decree a "first and important component" of change, but said legislators should seize the opportunity to impose a ban on all gifts, or make the state's current gift laws stricter.
"We have another one of those moments in time where it should be fairly easy for the legislature to do the right thing - and that is to restrict gifts or ban gift-giving altogether," said Kauffman.
He added: "I think it would be an incredible shame if we lost the opportunity to make the cultural change that is needed in the legislature."