WHEN THE Supreme Court decided last summer that under certain circumstances judges can hold secret sessions in criminal cases, some of its members suggested these would be few and far between. Unfortunately, their judgment has not proved right. Courtroom doors all over the country are banging closed now, and trial judges seem to believe they have power to act in secret almost any time they want to.

In Virginia, a trial was held in secret because the judge decided the defendant would be embarrassed if it were conducted in public. In North Carolina, a pretrial hearing in a murder case was secret because a lawyer said publicity about it would be embarrassing to him. In New York, the courtroom doors were closed for a pretrial hearing in a simple assault case because publicity would embarrass a suspect. In Ohio, a murder trial was conducted in secret because the judge said a public trial would harm the mental health of a defendant.

These are a few of the more than 100 secret court proceedings that have been listed by the Reporters Committee. In almost every state, efforts have been made to close the doors of some court. In at least 10 states, full criminal trials have been held in secret. In a few states, even post-trial proceedings have been held in secret.

We doubt that this full-scale retreat by trial judges into closed courtrooms was what the Supreme Court had in mind last summer. If it was, the country's judicial system is in big trouble; nothing is more likely to undermine the credibility and, thus, the integrity of the judicial system so rapidly as frequent secret trials.

If this is not what the judges anticipated or wanted, they have an opportunity in a case pending before them to change things. They ought to do so, admitting that they were wrong last summer and reestablishing the 200-year-old American tradition of open criminal proceedings.