Tension between the House ethics committee and the new Office of Congressional Ethics burst into plain view this month with a surprising accusation — that the OCE had concealed evidence that might clear a Member under investigation.

The Member is Rep. Sam Graves (R-Mo.) and his apparent offense is rather minor — for the second time, he invited a friend with whom he has financial dealings to testify at a hearing without disclosing the relationship.

He did it first in May 2004, when he was chairman of the Small Business Subcommittee on Rural Enterprises, Agriculture and Technology and invited two friends to testify about the promise of renewable fuels and tax incentives for ethanol and biodiesel.

The friends, Charlie Hurst and his son, Brooks Hurst, were identified as representatives of Golden Triangle Energy, but Graves did not disclose that he and his wife were investors in the ethanol cooperative.

When Roll Call reported on the lapse in 2007, Graves told the Kansas City Star, “Looking back on it, I probably should have— made the disclosure.

In March, Graves, now ranking member of the full Small Business Committee, invited Brooks Hurst back to testify on renewable fuels and once again failed to disclose his business connection.

This is evidently the matter that the OCE looked into and referred to the Committee on Standards of Official Conduct, commonly known as the ethics committee, for further review and possible action.

The OCE said that its inquiry produced “substantial reason to believe that a substantive violation may have occurred.— Graves issued a statement declaring that he would be vindicated.

What’s remarkable is the public smackdown delivered to the OCE by the ethics committee: the claim that the committee had identified “materials in the [OCE’s] report … that may contain exculpatory evidence which OCE never provided to Rep. Graves— and that the committee said it would provide.

The OCE responded “respectfully— that what it turned over to the committee came from Graves’ office and “the OCE would never withhold exculpatory information from a subject of an investigation and did not in this instance.—

The committee basically is accusing the OCE of lacking integrity — a damning charge that suggests tensions between the two bodies are even more serious than has previously been clear.

The six-member OCE, made up largely of estimable former Members, was established to restore confidence in the ethics process after years when the committee failed to investigate serious scandals.

Under Chairwoman Zoe Lofgren (D-Calif.) and ranking member Jo Bonner (R-Ala.), the ethics committee has launched enough probes to suggest that it is active, although we have yet to see any actual results in cases such as those involving powerful Members including Reps. Charlie Rangel (D-N.Y.) and John Murtha (D-Pa.).

We’re inclined to think that the OCE would not conceal evidence — why would it? — and suggest that the ethics committee produce some results, not impugn the integrity of a body with whom it is supposed to be cooperating.