THE MARYLAND General Assembly has a chance this year to restore some of the privacy that the Supreme Court has stripped away from ordinary, law-abiding citizens. It can pass a bill, introduced by Sen. Howard A. Denis, to give all citizens the kind of protection against "third-party" searches that Congress and related occupations.

The Denis bill would bar judges from issuing warrants authorizing the police to search the belongings of persons not suspected of crime, except in a few limited situations. If the police believe such a person does possess evidence of a crime someone else committed, they would have to seek it first through a subpoena.

The Supreme Court made this kind of legislation necessary three years ago when it upheld the constitutionality of a search of the offices of the Stanford Daily. No one who worked on the student newspaper was suspected of a crime, but officers prowled through files, wastebaskets, desks and photo laboratories in a fruitless effort to find something that would identify the persons who had been involved in a riot.

After two years of consideration, Congress passed the Privacy Protection Act last fall to protect from such searches journalists and authors who are exercising their First Amendment rights. That job limitation was partly due to objections by the Department of Justice and partly due to questions about the power of the federal government to cover other citizens.

No question exists about the power of state governments to grant equal protection to other citizens. Some -- notably, psychiatrists, social workers and ministers -- have as strong a claim for the sanctity of their files as do journalists. Other citizens, whether or not they receive confidential material from their clients or sources, ought to be spared the outrage of police searches unless they are clearly unavoidable.

The bill that Sen. Denis has introduced in Maryland would provide the needed protection for everyone without impinging unnecessarily on the ability of the police to find evidence of crime. It should be approved today by the Senate committee on judicial proceedings and promptly passed.