A Senate Judiciary subcommittee yesterday approved a balanced budget amendment to the Constitution that would limit federal spending and taxes.

The subcommittee on the Constitution, headed by Sen. Orrin G. Hatch (R-Utah), also reported out a bill setting up procedures for calling and convening constitutional conventions.

The balanced budget amendment, offered by Judiciary Committee Chairman Strom Thurmond (R-S.C.), was approved by 5 to 0. But Sen. Paul Simon (D-Ill.) voiced sharp reservations about the section limiting taxes to the rate of growth in national income.

The proposed amendment would require Congress to "adopt a statement for each fiscal year in which total outlays are not greater than total receipts." Congress could get around that rule and "provide for a specific excess of outlays over receipts" but only by a vote of "three-fifths of the whole number of both houses."

If approved by Congress, the amendment would have to be ratified by the legislatures of three-fourths of the states within seven years after its submission to the states.

Simon sought to strike the second section of the plan, which would restrict taxes. He said he thought it could "create real mischief" and warned that he could not continue to support the bill unless it is changed. He was voted down in the subcommittee, 3 to 2.

The amendment would require Congress to limit any increase in total receipts to "the rate of increase in national income in the previous year" unless an absolute majority in each house passes a bill "directed solely to approving specific additional receipts and such bill has become law."

Hatch rated the chances of winning full committee and Senate approval as excellent. "It does not write economics into the Constitution," he said. "It is a restriction on taxes and spending."

Simon said he feared that the tax restriction would lead Congress to cut back on needed programs, such as Social Security, in order to offset the impact of a vote for higher levies in other areas, such as an increase in the federal gasoline tax. He said he was afraid the need for an absolute majority in both houses to make an exception would prove too big a hurdle.

The proposed constitutional convention implementation act would provide for a 535-member convention, elected on the same basis as members of the House and Senate but excluding such lawmakers, whenever two-thirds or more of the states call for a convention to consider "the same subject matter" within a seven-year period.

Under the bill, a convention would sit for a maximum of six months unless Congress approved an extension. No convention could consider amendments "of a subject matter different" from that for which it was called. Proposed amendments would have to be ratified by three-fourths of the states as called for in the Constitution.

The subcommittee also approved legislation placing additional restrictions on the Freedom of Information Act by creating an automatic exclusion for information about organized crime investigations and expanding the number of records that the government can withhold on grounds of privacy.

Clearing its deck of another long-simmering item, the subcommittee reported out a "public schools civil rights act of 1985" that would prohibit lower federal courts from ordering any more school busing for racial desegregation.

Hatch said no hearings were necessary on his Freedom of Information Act bill because it is identical to one that died in the last Congress as a result of opposition in the House.

The administration-supported measure, which Hatch has been sponsoring for several years, would exempt more information from public disclosure by creating the new exclusionary rule for organized crime investigations, broadening the existing exemption for other law enforcement records, setting up a new system to protect claims of business confidentiality, and creating a special exemption for the Secret Service.

Spokesmen for press groups, including the American Newspaper Publishers Association, Sigma Delta Chi, and the National Association of Broadcasters, are opposed to the bill. Hatch said that the proposal is needed to "eliminate many of the serious flaws in the Freedom of Information Act," including its use by criminal elements