As he held a press conference in Philadelphia on Saturday, Mr Giuliani, the president’s personal attorney, was informed that Mr Biden had been declared the winner after claiming Pennsylvania and its 20 electoral college votes.
Mr Giuliani threw his arms to the sky and mocked the fact that US news networks had called the election for Mr Biden.
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“Oh my goodness! All the networks. Wow!” said the former New York mayor, sarcastically. “All the networks. We have to forget about the law. Judges don’t count.”
He added: “Networks don’t get to decide elections. Courts do.”
Votes of the US electorate decide the outcome of presidential elections.
Mr Trump has refused to concede and made repeated baseless claims about election fraud. Mr Giuliani vowed again that litigation from the Trump team would continue next week over the vote count in Pennsylvania.
“He’s not going to concede when at least 600,000 ballots are in question,” Mr Giuliani said on Saturday, referring to Mr Trump. There is no evidence for this claim.
At the press conference, the attorney was accompanied by three people, described as poll watchers, who alleged they were stopped from adequately monitoring ballot counting.
Mr Giuliani claimed to have statements from another 25 watchers, and said up to 50 others had similar tales but that they did not come to the press conference, as some were afraid of “retribution”.
Mr Biden crossed the winning threshold of 270 Electoral College votes with a win in Pennsylvania.
President-elect Biden currently has 290 electoral college votes to the president’s 214 count. A total of 270 EC votes are needed to win. Georgia, North Carolina and Alaska have yet to announce their final tallies.