Soviets Wary of Powerful U.S.-Style Presidency : Reforms: Some fear the new system won’t establish checks and balances to bar the rise of a dictator.

The Soviet Union, after years of disdainfully rejecting Western models, is fashioning its revamped presidency in part on the American chief executive. But political scientists warn that special precautions are needed to prevent a repeat of Russian history: the emergence of oppressive one-man rule.

Experts who helped draft the constitutional amendments concerning the office of Soviet president, which is likely to be approved by the Congress of People’s Deputies this week, note that many of the proposed powers match those held by the President of the United States.

But because the upheaval in Soviet politics over the last several months has left the entire parliamentary system in flux, some warn that presidents under the new system could take advantage of the confusion to become omnipotent. Lawmakers, still unpracticed in democracy, might be unable to prevent such a sweep to tyrannical rule, critics say.

Proposed powers, which experts say might permit a dictatorship in the absence of proper checks and balances, include the right of the president to issue a decree “binding on the entire territory of the country” and to unilaterally declare a state of emergency in a republic.

“It is not enough to clarify what powers the president should have,” said Victor I. Borisyuk, a chief adviser at the U.S.A. and Canada Institute, an academic institution in Moscow. “In fact, by itself, this is a mistake and will not create stability for us.

“We need to clarify several other things at the same time, primarily what exactly will be the powers and relationship between the various institutions intended to balance the president,” he said.

It is still unclear, Borisyuk and other political specialists note, which powers should be wielded by the 2,250-member Congress of People’s Deputies, the smaller Supreme Soviet whose members are elected from among the Congress’ deputies, and the local parliaments in each of the country’s 15 republics.

So the organs are likely to compete with each other and fail to act as a check on presidential powers.

“While (Mikhail S.) Gorbachev might not abuse the powers, who knows what will happen next year or even next month, or who will come after him?” Borisyuk said. Gorbachev is widely expected to be chosen as the first president.

The constitutional articles on the presidency to be considered by the Congress of People’s Deputies provide for some powers clearly based on those held by the American president.

* The president is to be elected initially by the Congress but thereafter by popular secret ballot. He will serve for no more than two five-year terms.

* The president will be able both to veto a bill outright--requiring a two-thirds majority in the Supreme Soviet to override that veto--or to use the equivalent of the American pocket veto to kill a bill simply by refusing to sign it during the legislative session.

* The president will have the power to commute death sentences, negotiate treaties and represent the country abroad.

* The president will appoint all top government and military posts and also will have the power to remove appointees.

Several proposed presidential powers have been opposed by nationalists in the Baltic and Caucasian republics and by progressive deputies who have formed an Inter-Regional Group that acts as a political opposition. Both the deputies and political scientists stress that the country must keep in mind abuses of power both by Russian czars and Soviet leaders.

For centuries, Russians and visitors to the country have described governments that held inordinate sway over the governed. In 1839, for instance, French nobleman Marquis de Custine visited Russia and described “the blind submission” of the people to Czar Nicholas I.

In 1936 the French writer Andre Gide echoed his countryman in describing Soviets during Josef Stalin’s bloody rule. He wrote that an all-powerful government was seeking total compliance and conformity from the people, and “what is most astounding is that this attempt is successful.”

“We have in our history no democratic tradition, no democratic mentality,” said Borisyuk. “The idea of a strong central power is deeply rooted in our past, and many, many people still want a strong symbol of power. We must beware.”

Several articles in the proposed amendments have elicited concern:

* The president is called upon to take “all the necessary measures to protect the . . . territorial integrity of the country.” Nationalists warn this could give the president the authority to oversee a crackdown against republics seeking to secede from the union, a right which is theoretically guaranteed by the constitution. Strong pro-independence movements exist in the Baltic republics of Lithuania, Latvia and Estonia, as well as in Georgia.

* The president has the right to declare a state of emergency in any locality, after simply advising the Presidium of the Supreme Soviet of the republic in question. This was intended specifically to help the president combat the rise in ethnic conflict which has troubled most of the country’s 15 republics. But critics have warned it could easily be abused.

* If there is discord between the two houses of the Supreme Soviet that the president cannot settle, he can dissolve the body. The ambiguous language of the article could, in theory, permit a president to simply dismiss a legislature that was effectively acting as a check on his powers.

In an effort to beef up the influence of the Supreme Soviet so it can act as a balance to presidential powers, Borisyuk and several other specialists have called for the outright dissolution of the Congress of People’s Deputies, arguing that it has become an unwieldy institution and is diluting the authority of the Supreme Soviet.

The Congress, to which representatives were elected from across the country, “was, just months ago, our main hope,” acknowledged Vladimir A. Toumanov of the Soviet Academy of Political Sciences, an adviser on the constitutional changes regarding the presidency.

“But times are changing with such rapidity we can already see it is slowing change and hampering our development into a real democracy,” he said.

Toumanov argued that the Soviet Union needs a strong president to deal with unprecedented problems--such as ethnic strife and the stoicism of middle-level bureaucrats who have blocked many of Gorbachev’s efforts to implement economic change.

“The situation in the country right now is very dangerous, and that is why we are in a hurry to create a strong president,” agreed Alexander Darchiyev, another expert at the U.S.A. and Canada Institute. “But at the same time I would like to see a strong system, not just a strong president.”

“We need, in fact, to make our parliament stronger than the American parliament, so the people can learn through the parliament a new idea for the Soviet Union--the idea of political pluralism and tolerance.”