THERE IS NO good reason to believe that President Nixon is telling the truth about the non-existence of two of the nine Watergate tapes. Nixon's delayed announcement of the tapes' loss, his ever-changing account of when he first discovered their absence, and the constant revisions of his explanation for why two conversations were never recorded all make the claim of non-existence immediately suspect.

To charge Nixon with lying about the non-existence of the tapes is tantamount to charging him with obstruction of justice. Such a charge is not inappropriate when leveled at the administration in Washington. Nixon has lied about the secret bombings of Cambodia, it was revealed this week that Nixon lied about his role in keeping an ITT anti-trust suit out of court, and there is every indication that Nixon and his cronies have been trying to lie their way out of the Watergate mess ever since June 17, 1972.

Judge Sirica must pursue his investigation into the circumstances surrounding the tapes' "non-existence." If the Nixon administration has taught us nothing else, it has taught us that Nixon's word cannot be taken at face value.

While Sirica's investigation continues, however, Nixon's travesty must be put to an end. Nixon must not be given further opportunity to put the presidential stamp on his lies. His removal from office is long overdue.