It would be heavy news in any state legislature, but when there are serious conflict-of-interest charges against a state senator in Virginia, it's high drama. State Sen. Peter K. Babalas, a Norfolk Democrat and the fourth-ranking member in that body, now faces criminal prosecution on charges that he violated Virginia's conflict-of-interest law. It is the first time a sitting legislator has been charged with such an offense; and the state lawmakers gathering yesterday for the opening of their 1986 session were more than a little aware of the case. For their sake and in fairness to Sen. Babalas, the decision to move to court is a good one. The sooner this case is resolved the better it will be for the General Assembly.

The move by Acting Attorney General William G. Broaddus comes a day after a finding by a senate ethics panel that Mr. Babalas "willfully" violated two sections of the law. The senator has maintained he did nothing wrong in acting as an attorney for Landbank Equity Corp. and casting his vote and the proxies of two other legislators to kill legislation regulating the second-mortgage industry in Virginia. In a one-year period, Sen. Babalas received more than $61,000 from this second-mortgage company.

The conclusion of the senate panel -- with which Mr. Broaddus says he agrees -- was that "taken as a whole, the record supports a finding that there is a reasonable basis to conclude that Sen. Babalas accepted money for services involving his position as a senator, that he used his position as a senator to benefit his client, that his fees for services to Landmark covered his use of his legislative position on Landmark's behalf." Specifically, Mr. Broaddus says his office will pursue charges that Mr. Babalas violated a section of the law prohibiting officials from voting on issues in which they have a personal interest, as well as allegations that the senator accepted a "professional opportunity" knowing that "there is a probability that the opportunity is being afforded him with intent to influence his conduct in the performance of his official duties."

Mr. Babalas has chosen to take his seat in the senate, and under state law he is immune from standing trial while the legislature is in session. That is his right, but it won't make it easy for him or his colleagues as issues come up for votes from now on.