Congress, high-ranking bureaucrats and judges could receive a pay raise of as much as 7 percent later this year because of an amendment quietly approved by the House Appropriations Committee.

The increase would affect everyone in the executive, judicial and legislative branches making more than $47,500 a year (GS18s and above), including Cabinet and subcabinet levels, members of Congress and their top staffers. Members of Congress now make $57,500 a year and, if they receive the full 7 percent increase, they would make $61,525.

The amendment is part of the legislative appropriation bill and is expected to come to the floor next week. The pay issue is expected to be highly controversial.

Rep. George M. O'Brien (R-Ill.), an Appropriations Committee member, said he did not learn of the amendment and its consequences until Wednesday, the day after it was adopted. He said he will oppose the action.

"I don't think this is the time to give ourselves a pay raise. Even if the job is worth the money, there's a question as to whether the issue is worth the job," O'Brien said, referring to the criticism a congressional pay raise always receives from the press and public.

O'Brien said he traditionally opposes such pay raises because hedoesn't believe members of Congress should vote a pay increase for the same term in which they are serving.

But the sponsor of the amendment, Rep. John P. Murtha Jr. (D-Pa.), said, "This is a cap, a limitation." Each year, under the Comparability of Pay Act, President Carter looks at federal pay levels and private industry levels and inflation rates and decides how large an automatic cost-of-living increase federal workers should get.

Last year he ordered a 5.5 percent increase. But Congress, concerned because it was an election year, froze its pay and the pay of the supergrades in the other two branches at the previous year's level.

The new amendment would end the pay freeze imposed last year, but would limit any increase covering both years to 7 percent.

Murtha contends that without this "cap" last year's increase and this year's too, would add up to an increase of about "12 or 13 percent."

Murtha said inflation was running at about an 18 percent rate for the two years, so he did not consider a 7 percent increase unfair. Asked if Congress should be included in the pay raise Murtha said, "Congress is in the same position as everyone else."

But he admitted, "I don't know what they'll do on the floor of the House."

Rep. Adam Benjamin Jr. (D-Ind.), chairman of the legislative appropriations subcommittee, said, "This bill always brings out the frustration in every member, and I'm sure this is just one of the many things they'll have to shoot at.

"My feeling is that we ought to be the same as everyone else in the government. We work long hours and have tremendous responsibilities."

Benjamin said he would oppose any effort to deny the raise to members of Congress but give it to other federal employes. "I don't think we ought to separate ourselves out. But there's no doubt we'll be the ones subject to criticism, not the judges or the bureaucrats."

Benjamin also said he would make no attempt to have the Rules committee deny the House a vote on the matter, as has occasionally been done on pay raises in the past.