A Virginia House committee, ignoring objections that its actions would encourage the use of marijuana, today overwhelmingly approved legislation that would ease first-offense penalties for possession of small amounts of it.

The measure, as initially approved by the Senate, would eliminate jail sentences for first offenders. But the House committee today amended the bill to provide for a jail term of 30 days and/or a fine of $500 as maximum punishment for simple possession of a half ounce or less of marijuana.

"The use of marijuana has risen to epidemic proportions and moved from the ghetto to middle-class America," said Marian Anderson of the Virginia Farm Bureau, who urged the House Courts of Justice Committee to resist pressure to reduce penalties for possession and use of the drug.

Without discussion, however, the committee voted 11 to 1 to report the bill to the House floor.

Virginia's current marijuana laws provide for a maximum penalty of one year in jail and a $1,000 fine for possession of marijuana for personal use.

Ten other states have lessened the penalties for such first offenses.

The measure would also set a range of maximum penalties of up to 30 years in prison for distribution of the drug, depending upon the amount involved. It also would permit physicians to prescribe marijuana to treat symptoms of certain diseases, including glaucoma and cancer.

Roy Scherer, director of Virginians for the Study of Marijuana Laws, a group that wants to decriminalize use of the drug, supported the measure as making "some progress," but said his organization would like it to go even further.

As General Assembly committees rushed to meet a midnight deadline for committee actions, the Senate Privileges and Elections Committee confounded supporters of placing party labels beside candidate names on ballots by defeating their proposal, 5 to 3.

The bill had been approved overwhelmingly by the House of Delegates and appeared headed for easy passage in the Senate before today's surprise committee vote.

Republican Gov. John N. Dalton vetoed a party designation bill approved by the assembly last year, but its supporters believed they had enough votes to override a veto this year if the bill went to the governor by Saturday, the last day of the legislative session. Bills submitted to Dalton after Saturday can be vetoed without a chance for the Assembly to override.

Del. Richard R.G. Hobson (D-Alexandria), chief patron of the party designation measure, said it was sent back to committee for certain defeat because many conservative Democratic senators did not want to risk running under their party's label this year in the wake of recent Republican victories in statewide elections.

Hobson said Virginia is one of only two states that fails to provide for party designation of candidates on ballots. The other is Nebraska, where state elections are nonpartisan.

In other action, the House Courts of Justice Committee, quietly and without discussion, voted 7 to 4 to kill legislation that would have created a special judicial nominating commission to help fill bench vacancies.

The measure had been approved by te Senate. Its sponsor, Sen. William F. Parkerson Jr. (D-Henrico) told the House committee earlier this week that he was trying to emphasize merit qualifications over political connections when the General Assembly chooses judges.

"The legislative process as we see it today doesn't permit us enough time to do an in-depth study of the judicial candidates," said Parkerson, whose bill sought to have potential judges nominated and screened by a special commission composed of one member from each congressional district in the state and five lay persons.

The Assembly would still make the final selection and House and Senate committees would continue to interview the nominees.

But House members on the committee, which had been expected to kill Parkerson's bill, argued during a hearing on the measure that the present selection process is working well enough and that assembly members should retain strong control over judicial selections.

Also today, the House Conservation and Natural Resources Committee killed the Senate-approved Coastal Resources Managemcnt Act that would have set up procedures for protecting sand dunes and unvegetated wetlands from development disturbances.

The Senate Couts of Justice committee voted 9 to 5 Monday night against a divorce law reform bill that had been passed last month by the House.

The bill, sponsored by the nine women members of the House, would have given each spouse a claim to share in the accummulated net worth of a marriage regardless of monetary contribution.

The committee rejected the bill on the grounds that it would be an insignificant change in existing Virginia divorce law, which some senators said already treats spouses and their property equally in divorce cases.