By Martin Asser BBC News

Opponents are calling the amendments the "death of Egypt"

Emergency powers were implemented in 1981, after the assassination of President Anwar Sadat, and have been in force ever since.

But critics of Mr Sadat's enduring successor, Hosni Mubarak, say the amendments will enable a replacement of emergency laws with something just as authoritarian - but permanent.

The 34 new articles were approved by a vote in parliament - dominated by members of the ruling National Democratic Party on 19 March.

The amendments will write into permanent law emergency-style powers that have been used to violate human rights Amnesty International

A week later they were put to a popular vote. Government officials said they were approved by more than three-quarters of voters, although the turnout was low - 27% according to official figures, much lower by other independent groups.

The opposition, led by independent supporters of the banned Muslim Brotherhood movement, boycotted the vote, saying the lightening referendum did not give them a chance to mount a proper "No" campaign.

Demise of socialism

The government says the constitutional changes will enhance Egypt's democracy and allow it to fight terrorism more effectively.

Article One, for example, changes Egypt from a "democratic, socialist state" based on an alliance of workers to "a democratic system based on citizenship".

Mr Mubarak has been in power more than a quarter of a century

The socialist economic system previously enshrined in Article 4 becomes a system "based on freedom of economic action... safeguarding ownership and preserving workers rights".

The anachronistic Article 59 - "safeguarding socialist gains is a national duty" - becomes a much more fashionable "conserving the environment is a national duty".

One of the most controversial amendments, Article 179, gives the president new powers to refer terrorist cases to any judicial authority he chooses - including military tribunals whose verdicts are not subject to appeal.

It also says the authorities may override three other articles protecting individual freedoms and privacy.

Dynastic transfer

Some amendments appear to be specifically written to perpetuate the rule of Mr Mubarak's National Democratic Party.

In fact, his critics say they are meant to pave the way to a dynastic transfer of power to Mr Mubarak's son, Gamal, currently a high-flying official in the NDP.

The government is accused of abusing the emergency laws

Article Five, for example, gives a nod towards a "political regime based on the multi-party system".

But it also bans "any political activity or political party based on any religious background or foundation".

It seems hardly a coincidence that the strongest challenge to the NDP comes from the Muslim Brotherhood, which is already banned but tolerated by the authorities. Now it is actually unconstitutional.

Article 88, which previously stipulated supervision of elections by members of the judiciary, has also been rewritten to remove that control.

This seems connected to a high-profile struggle last year when two senior judges unsuccessfully pressed for an inquiry into alleged electoral fraud during the general election in 2005.

Meanwhile Article 7 requires presidential candidates to be nominated by parties with at least 3% of elected members of parliament - another insurmountable obstacle for the Brotherhood.

Constraints

Amnesty International, a London-based human rights group, warned that the amendments would "write into permanent law emergency-style powers that have been used to violate human rights" since 1981.

Article 179 seems particularly draconian, stating that Articles 41, 44 and 45 (paragraph two) of the constitution must not "hamper" investigations into terrorist crimes.

These articles prevent detention without judicial authorities' permission, police searches without a warrant and eavesdropping on personal communications.

It is unclear how fully the government will use the new powers enshrined in the amendments.

Critics like Amnesty expect more of the same, in a country where political opponents are already subjected to numerous constraints preventing them from competing on an equal footing with the ruling party.