IN A CONSTRUCTIVE shift away from long-prevailing policy in Maryland, Gov. Harry R. Hughes has come out squarely against building a big new prison in the state -- calling instead for more community rehabilitation facilities and better probation and parole programs. This is the direction in which the governor's new corrections commissioner, Gordon D. Kamka, has been headed since taking over, and it makes sense. But already there are indications that the governor is in for a confrontation with the General Assembly -- or at least with certain members who have the wrongheaded impression that the administration is urging the indiscriminate release of dangerous criminals.

For years in Annapolis, the only debate was where the new prison should be built, not whether. But Gov. Hughes has said no to a proposed 890-bed medium-security facility, endorsing a task-force reprot commissioned by Mr. Kamka. Among other things, this report notes that construction is under way of facilities to accommodate 1,023 inmates at correctional annexes in Baltimore, Jessup and Hagerstown. In addition, the task force urges the hiring of 125 more probation agents to allow an increase in the state's probation rate and expansion of rehabilitation centers for minimum-risk inmates -- which now handle about 255 inmates, and which Mr. Kamka believes should accommodate 2,400.

Though the Assembly would find it difficult to force construction of a prison that the governor doesn't want and won't pick a site for, the lawmakers have ways of playing games with the corrections budget. The first signs of this have been in committees, where there have been votes to kill pay raises for parole agents and to cut money proposed for community correction centers and for the Jassup facility. Add to this the familiar "anywhere-but-here" constituencies that rally against community correctional facilities and you have the makings of a difficult time for the administration.

But merely building more huge warehouse-style prisons hasn't done any good. For that matter, such facilities may actually aggravate the crime problem because inmates return to the streets more dangerous than when they left. According to the task force, Maryland has the fifth-highest rate of incarceration in the country -- 198 inmates for each 100,000 residents.That's more than twice the rate of the neighboring states of Virginia, Pennsylvania, Delaware which the courts have already declared to be cruel and unusual punishment -- and which the state has been ordered to correct by next year. Rather than squabbing to perpetuate stale and ineffectual policies, responsible lawmakers should support the administration's efforts for constructive change.