ARTHUR LEE WHITFIELD has been locked up for 23 years for two rapes committed in 1981. The rapes were committed 45 minutes apart in Norfolk, and both victims identified Mr. Whitfield as their attacker. After conviction by a jury in one case that netted him a 45-year sentence, he took a plea deal in the second for an additional 18 years. This week he was freed, the state having concluded based on DNA evidence that he is innocent.

Mr. Whitfield's exoneration through court-ordered DNA testing might not have been possible only a few years ago, when any testing of evidence in old cases depended on a governor's whim. Only reforms passed by the General Assembly allowed him to go to court -- unaided by a lawyer -- and ask whether any evidence remained to test. Even under current law, it might have taken much longer had Norfolk Commonwealth's Attorney John R. Doyle III not acted honorably and facilitated testing and a quick release in light of the results.

Most important, however, it would not have been possible had a now-deceased worker at the state crime lab -- Mary Jane Burton -- not habitually saved biological evidence in the cases she worked on. By so bucking lab practice, she preserved material that in Mr. Whitfield's case -- and in two other cases so far -- has proven that an innocent man was wrongly convicted. Imagine how many other innocent people must be imprisoned in the commonwealth if such unlikely happenstance can reveal in short order three different cases of wrongful conviction. Ms. Burton's other preserved samples need to be examined.

Consider also how many more innocent people might be freed if the General Assembly took reform to the next level. This year the legislature relaxed the noxious 21-day rule, which said that newly discovered evidence couldn't be considered once three weeks had passed after conviction. But the reform is too restrictive, and legislators rejected the efforts of Gov. Mark R. Warner (D) to permit easier access to the courts by inmates who claim innocence. The anemic reforms so far have demonstrated that innocent people are rotting in Virginia prisons, and they have not produced the flood of frivolous litigation about which opponents warned. All plausible innocence claims should have a chance to be aired.

The legislature has done little to improve defense lawyering for poor people accused of crimes and to level the playing field at trials so that wrongful convictions can be avoided in the first place. Until basic change takes place in Virginia's criminal justice system, tragedies such as Mr. Whitfield's are a certainty.