Virginia's generally harsh marijuana laws should be softened, a wide range of witnesses including Fairfax County Police Chief Richard A. King told a joint legislative committee yesterday.

Even Fairfax Board Chairman John F. Herrity, the Republican candidate for Congress from the 8th District, said he agreed with King that the penalty for distribution - five to 40 years - is probably too harsh in many cases.

At the same time Herrity said there should be no lessening of the present penalty for users - up to one year in prison - at this time.

King did not appear in person before the committee, which is studying, possible revision of the state's laws governing the widely used drug, nor was his testimony read into the record.

The subject is a controversial one in Virginia as it is elsewhere, and public officials have been wary of appearing too far ahead of public opinion.

But King said in written testimony: "I personally would prefer to see a less severe maximum penalty in favor of absolute mandatory minimum penalties involving appropriate periods of incarceration and significant fines."

For example, King said in an interview, "it may be inappropriate for someone to get 40 years for distribution. I am more inclined to lean toward a lesser, but specific, mandatory sentence, say, five years."

King also said in his testimony that state law-enforcement officials "may be on fundamentally unsound ground" in concluding that a suspect is a distributor solely because he is in "possesion of a specific quantity of drugs." Virginia law does not specify that offenses for marijuana distribution or intention to distribute must include evidence other than the quantity of the drug.

King's proposal for a reduction in the penalty for distribution was generally supported by Herrity. While Herrity did not discuss the issue specifically in his own testimony, he said in an interview, "I go along with the chief when there are small amounts of marijuana involved. But I think the bigtime distributor should still be liable to five to 40 years.

In his prepared testimony, Herrity took a hard line, opposing any lessening or elimination of penalties for use of marijuana. Virginia law provides for a sentence of up to one year for use, although a judge can suspend the sentence of a first-time offender and put him on inactive probation that can lead to expunging of the conviction.

"Any lessening of the penalty for the use of marijuana is not warranted at this time, "Herrity said. But while discussing the medical safety of the drug, Herrity did say "prudence requires us to wait until the weight of the available evidence points more clearly to the absence of danger before moving to permit wider usage."

Though she said she was opposed to legalization, Del. Gladys B. Keating (D-Fairfax) told the committee that "general revision of the laws in order."

She also said Virginia should join the three states - New Mexico, Florida and Illinois - that permit marijuana to be used medically in a limited way, such as in treatment of glaucoma (a blindness) and as an adjunct of cancer therapy with nausea-causing drugs.

While declining to say what revision he would support, the chairman of the joint committee, Sen. Frederick C. Boucher (D-Abingdon), said in an interview: "We have some real disparities in how the present laws are applied."

Boucher said that although under the law police can issue a citation for simple use - a procedure also used for most traffic violations that doesn't require the suspect to be booked and fingerprint - this is not done uniformly. Nor, he said, do judges uniformly suspend the sentence of first time offenders and put them on inactive probation.

Boucher indicated that any changes of the law probably would involve making the procedures mandatory.

None of the police officials who presented testimony, including King, supported elimination of criminal penalties for simple use.

Sgt. Joe Tavares of the Vienna Police Department said, "I feel I must do everything possible to stop this terrible thing (use of marijuana)." Referring to testimony in support of lesser penalties and legaliazation, he said, "A lot of what I heard this morning is a lot of bull. Marijuana, pure and simple, is garbage . . . Anybody who tries to push it should be in jail."

A group of officials from the Virginia office of NORML, the national lobby for marijuana legalization, also testified and urged that all criminal penalties for use, cultivation and small-scale distribution be eliminated.