CAIRO — Egypt’s Supreme Constitutional Court ruled on Sunday that the laws that governed the election of the country’s only operating house of Parliament as well as the body that drafted the country’s postrevolutionary constitution were invalid.
While the ruling is unlikely to have any immediate practical effects, it further erodes the legal standing of President Mohammed Morsi and the legislature, which is dominated by the Muslim Brotherhood, at a time when they are struggling to run the country and ease Egypt’s economic distress.
The ruling is also a new volley in the battle between Egypt’s rulers and the country’s judges, most of whom were appointed under the former president, Hosni Mubarak, and distrust Morsi and his allies.
The Freedom and Justice Party, the Muslim Brotherhood’s political wing, has emerged as Egypt’s strongest political force since the revolution that toppled Mubarak in 2011, winning the presidency and the largest share of seats in both houses of Parliament.
But it has faced frequent challenges over its handling of the post-Mubarak transition.
The opposition says it ignores other viewpoints and uses its political muscle to advance an Islamist agenda, and the courts have emerged as a rare check on the Brotherhood’s power from inside the government.
The Brotherhood and the judiciary have been battling in recent months over a proposed law that would lower judges’ retirement age to 60 from 70, a measure that could force more than 3,000 judges to leave the bench.
The opposition and most of the judiciary argue that the measure would allow the Brotherhood to install judges who support its political program.
With Sunday’s ruling, however, the judiciary struck back, challenging the Brotherhood’s legitimacy on two fronts.
In one, the court ruled that the law that governed the election of the upper house of Parliament was unconstitutional. That body, known as the Shura Council, is meant to be an advisory body, and its members won their seats in an election that drew only about 7 percent of voters.
The Shura Council’s role was then expanded to include legislative powers when the constitutional court disbanded the lower house last year.
The court said the Shura Council could continue to function until the election of a new lower house, but the ruling will cast a shadow on the legitimacy of any laws it passes.
A date has yet to be set for new elections, though they are expected to take place this fall.
The court also ruled that the 100-member assembly that drafted the country’s new constitution was illegal. That body has disbanded, and the constitution was approved in a referendum late last year.
The court appeared to accept the legitimacy of the constitution, though the ruling is likely to strengthen the arguments of those who say that Islamists dominated the constitutional process and ignored the views of many Egyptians.
“From a legal point of view, and from a legitimacy point of view, this ruling will weaken the Morsi administration,” said Emad Shahin, a political scientist at American University in Cairo.
A third part of the ruling also limited the president’s power by denying him the right to authorize arbitrary detentions under Egypt’s emergency law.
That measure was a particularly hated tool of the Mubarak government because it granted the security forces exceptional powers that were often used to crack down on dissidents.
Morsi appeared to accept the court’s ruling on Sunday while brushing off any doubts about the new constitution’s legitimacy.