BY ROBERT NOVAK SUN-TIMES COLUMNIST

Rep. Dan Burton's House Government Reform Committee hearing, scheduled for Wednesday but postponed until February, will continue months of rancor between old Republican comrades. George W. Bush and John Ashcroft have given an excellent imitation of Bill Clinton and Janet Reno by withholding information from Congress. Indeed, they have surpassed their Democratic predecessors in defying the legislative branch.

While President Clinton was trying to undermine investigations of his own campaign finance abuses, President Bush has ruled against the Burton committee's access to old scandals unconnected to him. The Bush team has seemed to back away from an earlier blanket rejection of all congressional subpoenas, but its claim to invoke executive privilege on a case-by-case basis is suspect. Incredibly, it refuses to give up documents about the FBI's Boston office condoning lawbreaking.

Nobody is more distressed by this arrogance than Burton, a true-blue conservative Republican from Indiana who wanted no fight with his administration. Nevertheless, he insists his investigation ''really needs to be done'' and cannot be blocked by government lawyers.

The blockage stunned Burton and his staff last summer when they sought government documents in two areas: first, then-Attorney General Reno's rejection of Justice Department recommendations to investigate Clinton campaign scandals; second, FBI misuse of mob informants in Boston decades ago. The message from Attorney General Ashcroft and White House Counsel Alberto Gonzales was blunt: Congress never again will have access to any documents reflecting deliberations inside the executive branch.

During a heated Burton committee hearing Dec. 13, Justice Department Criminal Division chief of staff Michael Horowitz modified this hard line by promising a case-by-case analysis. But it soon became clear that no case could ever meet the test. If FBI abuses in Boston failed, what case could succeed?

In Boston, Joe Salvati went to prison for 30 years on murder charges because of lies under oath by star FBI informant Joe Barboza; the FBI knew Salvati was innocent but wanted to protect Barboza. Stephen Flemmi allegedly committed murders over two decades while informing for the FBI and was not prosecuted. Burton wants to know why killers were protected.

''I believe that congressional access to these documents would be contrary to the national interest,'' Bush said Dec. 12 while invoking executive privilege. Burton's response in a Jan. 3 letter to Ashcroft: ''It eludes me how it is in the national interest to cloak this dark chapter of the Justice Department's history in secrecy.''

Reading ample correspondence between Burton and government lawyers makes the Bush team's intransigence look identical to Clinton's. Indeed, a Dec. 19 letter from Assistant Attorney General Daniel J. Bryant appeared to defend Reno's refusal to cooperate. Bryant suggested that Reno had satisfied the committee with an oral interview, which was wholly unsatisfactory.

For Bush's Justice Department to align itself with Janet Reno is drenched in irony. James Wilson, the Burton committee's chief of staff, worked for Michael Chertoff in the 1995 Senate investigation of Whitewater. Chertoff, assistant attorney general running the criminal division today, clashes head-on with Wilson. As a tough prosecutor, Chertoff is regarded by former Capitol Hill colleagues as the real source of this intractable policy.

Burton has come under attack from some conservatives because of praise from Democratic Representatives Henry Waxman and Barney Frank for opposing the pretensions of executive privilege even when a Republican president is responsible. Those critics want Republicans to accept and actually imitate the arrogance that habitually comes with executive power.