More than a decade and $21 million after it began, the final and longest-running independent counsel investigation in U.S. history ended yesterday with allegations from the prosecutor that "a coverup at high levels of our government" prevented him from bringing further charges in the case of Henry G. Cisneros, former secretary of housing and urban development.

In a 474-page report, independent counsel David M. Barrett conceded that he was "not able to say with certainty whether any criminal laws were broken" by government officials in his inquiry of possible tax violations by Cisneros. But he alleged that officials in the Justice Department and Internal Revenue Service "resisted our efforts to investigate" the possibilities.