Argentina's Supreme Court has struck down key elements of a judicial reform the government hoped would rapidly make the courts more responsive to majority rule.

The court says it's unconstitutional to require direct popular elections for an expanded magistrates' council that hires and punishes judges. The law would have expanded the council from 13 to 19 members and make it so that whatever party wins congress would be able to name a majority on the body.

But the high court said Tuesday that this would break the balance of powers in Argentina's democracy, compromise judicial independence and weaken citizens' rights by distorting the electoral process.

With a 6-to-1 majority, the justices also said such changes can't be done by passing laws, and instead require amending the constitution.