President Hugo Chavez's campaign over the past four years to remake the political landscape in Venezuela has reduced key government institutions to a shambles, leaving Chavez and his opponents without trusted legal bodies to resolve their dangerous standoff and end a crippling 15-day-old national strike.

As increasing social and economic unrest raises the threat of violence, Venezuela's highest court, the national legislature and the elections board have all become politically suspect. Their impartiality has been undermined by Chavez's efforts -- some successful, others not -- to enlist the officials who run them on behalf of his leftist program.

Any solution to the crisis would likely have to be endorsed by at least one of those institutions. But as of now, they are all on one side or the other, either striking in support of the opposition or in legal limbo because the standoff has frozen political reforms -- even those already approved by parliament.

The institutional weakness has left Venezuela without a reliable national referee. As a result, it has been left to international mediators to look for legal ways to avoid a repeat of last April, when a national strike and street violence killed 18 people and led to Chavez's brief ouster in a military-led coup. The main avenue under consideration now is moving up national elections, currently set for 2006.

Cesar Gaviria, secretary general of the Organization of American States, has tried to play the role of impartial mediator in promoting talks between Chavez's government and the organized opposition over the past five weeks. But even his neutrality has been questioned, mostly by a frustrated opposition, as the strike has hardened views on both sides.

Today, in a preview of an increasingly provocative opposition strategy to force Chavez to resign or call early elections, large groups of government protesters fanned out to block highways and avenues across Caracas, the capital. Angry pro-government groups met them in several places and a stretched-thin police force used tear gas and rubber bullets in a struggle to keep the rival demonstrators apart.

"The political crisis has to a certain extent gotten in front of the political institutions' ability to manage it," said Thomas A. Shannon, a deputy assistant secretary of state, after a two-day visit here last week. "That's why what's happening at the negotiating table is so very important, because if a solution is not found, we could be on the edge of some larger social confrontation for which we would have no idea how it would go."

Promising a "social revolution" with his 1998 election, Chavez pushed a series of successful referendums that gave the country a new constitution, a unicameral legislature and several new "citizen powers" designed to keep an eye on the government.

In doing so, Chavez sought to dismantle a relatively closed two-party system that had dominated political life here for four decades. He took control of the National Assembly, packed the supreme court and the National Electoral Council with political allies and pushed a program that riled much of the powerful upper class.

A former army colonel, Chavez also turned to the 80,000-member armed forces as a stand-in political party, appointing many of them to civilian government posts and giving them the right to vote for the first time.

His political opponents say Chavez violated the constitution's separation of powers guarantee. The most glaring example, they say, came in November 2001, when the president decreed 49 laws under emergency powers given him by the legislature. Those included such apparently non-urgent items as land reform and an energy law that gave the government greater control of the vital oil industry.

A month later the opposition called its first national strike.

Although Chavez has lost influence within the supreme court and the legislature over the past year, nearly every institution is now viewed as partisan. Even the Catholic Church, traditionally a conservative force here, has lost its ability to serve as impartial mediator after unsuccessfully opposing Chavez on his constitutional recognition of other religions.

"Right now you need a referee, something trustworthy, neutral," said Ismael Garcia, a congressman from the pro-government Podemos party. "And right now we don't have that."

At the center of any future resolution is the National Electoral Council, but the five-member panel is serving only on an interim basis, pending implementation of a new election law passed last month.

The council voted last month to allow a non-binding referendum in February on Chavez's rule, a move the president declared unconstitutional. The decision was overturned the same day by the supreme court for failing to have the required four votes. The opposition immediately condemned that ruling as partisan. Then, a few days later, the council approved it with the required four votes -- prompting Chavez to object that the commission was biased against him.

The solution would appear to be simple: Implement the new election law, which calls for a 21-seat electoral council with members from the government, opposition and civil society. But the National Assembly has been unable to meet to begin discussing appointments because of a walkout by opposition legislators in support of the strike.

Without an impartial government venue to settle differences, Chavez and the media have emerged as the key protagonists. The media openly oppose the president. Chavez has responded by calling media owners "fascists" trying to overthrow his government.

Roy Chaderton, the foreign minister and a government negotiator, said in an interview that any agreement on early elections would have to include guarantees that Chavez would have "fair access" to the media.

"How do you run a campaign when the major media now calling the president a killer are against it?" Chaderton said. "I'm not saying the government hasn't made its share of mistakes. But in a democracy you pay for those in fair elections."

In tearing down old institutions, Chavez has also built new ones. The government-sponsored Bolivarian Circles, supposedly small neighborhood advocacy groups, have emerged as the vanguard of pro-Chavez forces in the streets and are highly distrusted by the opposition.

The military could again emerge as the most important institution here if fresh violence breaks out, but it, too, is divided.

By putting the armed forces to work on behalf of his program -- using them to paint public housing, supply neighborhood markets, and build roads and bridges -- Chavez deepened traditional divisions between the conservative officers corps and lower ranks with humbler roots. The split was apparent in April when, two days after the coup, soldiers loyal to Chavez rebelled against the interim government that had been installed by senior officers. Chavez returned and has since purged much of the senior officer corps.

Venezuelan soldiers line up outside a police station in Caracas to separate opposition protesters and supporters of President Hugo Chavez on the 15th day of a national strike.Above, supporters of president clash with Chavez foes blocking a highway to push their demand that he step down or call early elections. At left, police, who used tear gas and rubber bullets to keep rival protesters apart, corral a Chavez supporter.