Liberal Party member of parliament Camilla Lindberg abstained, making her the only MP from the governing centre-right coalition not to vote in favour of the law.
But the opposition was quick to announce that the last word had not yet been spoken on the issue. Anders Karlsson, chairman of the Social Democrats' parliamentary defence committee, said his party would rip up the law if voted into power at next year's election.
"We'll rip it up, redo it, and do it right," he said.
The law had been the focus of the autumn season's first parliamentary debate earlier in the day, as politicians once again argued over the amended bill.
"Are we really, in a democratic country, going to implement a system which entails wire tapping the masses?" the Left Party's Alice Åström asked her colleagues in the Riksdag, according to the Svenska Dagbladet (SvD) newspaper
The controversial law gives sweeping surveillance powers to Sweden's National Defence Radio Establishment (Försvarets radioanstalt – FRA).
Despite extensive criticism from the public and the opposition parties, as well as a slew of internal challenges from prominent politicians in the centre-right Alliance government, the bill – referred to as the FRA-law – initially passed in June of last year.
An additional round of negotiations last September resulted in a number of amendments, including one calling for the creation of a special court which would rule on exactly what sort of cable-bound communications traffic FRA would be able to monitor.
While the changes were meant to assuage the FRA-law's many critics, the government's efforts to update the bill haven't swayed everyone, including longstanding opponent and Riksdag member Camilla Lindberg of the Liberal Party (Folkpartiet).
“I'm all alone in my party and as far as I know there are no other centre-right parliamentarians who aren't going to vote yes” to approve the amendments, Lindberg told the TT news agency ahead of Wednesday's debate.
According to Anders Karlsson, the government isn't interested in creating a just law, and has made no attempt to reach across party lines to develop a compromise that would satisfy political opponents.
“Personal privacy has been trampled in the name of political prestige,” he said.
The Green Party's Peter Rådberg claimed the FRA-law was “one of the most important questions of our time”.
“The state is going to get unlimited power to monitor citizens' data traffic,” he warned.
Karin Enström of the Moderate Party countered that the opposition is trying to spread horrifying rumours about the government and the centre-right parties behind the proposal.
She said the opposition's demand to appoint another commission to investigate the issue is simply a delay tactic meant to “bury the issue for several years”.
The law, which went into effect in January 2009, gives FRA -- a civilian agency despite its name -- the right to tap all cross-border internet and telephone communication.
Human rights organisations, politicians, the media and even the former head of the Swedish intelligence agency Säpo have vehemently criticised the legislation in both its original and amended form, citing fears of civil liberties violations and the creation of a "big brother" state.
Among other things, the amendment specifies that only the government and the military can ask FRA to carry out surveillance, that a special court must grant an authorisation for each case of monitoring, and that all raw material must be destroyed after one year.
It also limits eavesdropping to cases defined as "external military threats", "peacemaking or humanitarian efforts abroad", "international terrorism", and "development and proliferation of weapons of mass destruction", among others.
It also bars FRA from monitoring emails where both the senders and recipients are in Sweden, after critics pointed out that even emails sent between two people in Sweden can cross the border to be transmitted by servers located abroad.
Those who have been monitored must also be informed.