Could US election be decided in the courts?

Democrats and Republicans were gearing up Wednesday for a possible legal showdown to decide the winner of the tight presidential race between Republican Donald Trump and Democratic challenger Joe Biden.

Trump declared overnight he was ready to go to the US Supreme Court to dispute the counting of votes, as the results remained unclear in several key states, notably Pennsylvania.

Trump's threat raised the specter of the election being ultimately decided, as in 2000, by a high court ruling on how states can tally votes or conduct recounts.

The legal problems are mainly tied to the Covid-19 pandemic. Social distancing put a premium on being able to vote by mail.

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Each state sets its own voting rules, and many adopted or expanded mail-in vote programs. That required changing rules on how and when mailed ballots would be collected, verified and tabulated.

To accommodate millions of mailed ballots, state legislatures and election authorities extended the periods for receiving ballots, due to an overburdened US Postal Service, added time to count the votes, and took other steps to make the process easier.

Expecting that more Democrats -- who have by and large adopted a more cautious approach to Covid-19 -- would prefer to vote by mail, Republican groups around the country filed hundreds of lawsuits to block such rule changes, saying they violated existing statutes.

Some of those suits could be pursued in the seven key states where the vote count remained extremely narrow Wednesday, in some cases with ballots still arriving in the mail.

"It's clear that both candidates believe they still have a chance to win, so the fight is very much going forward. And the fight may take place in courts," said Ohio State University election law expert Ed Foley.

As in Florida in 2000, the challenges will focus on what ballots are legitimate.

Already before election day, Republicans sued over whether states like Michigan and Pennsylvania can legitimately count ballots after November 3 election day, or count those which arrive by mail after election day.

Trump has claimed repeatedly, without offering evidence, that ballots counted after election day, particularly those in key state Pennsylvania, would be "fraudulent."

Pennsylvania is particular target because, unlike Michigan and others, it agreed to sequester ballots that arrive by mail after November 3, making them clear targets.

Republicans are also challenging oversight of the counting of mailed votes, if ballots have correct postmarks, and policies to allow voters to "cure" their mailed ballots to prevent them from being discarded due to incomplete forms or unclear signatures.

All of those issues could give challengers the ability to disqualify individual or whole groups of ballots.

In Wisconsin -- where early returns show Biden leading by about 20,000 votes, within the one percent margin needed to request a recount -- Trump's campaign said Wednesday it will demand one.

But experts say neither party is likely to go to court unless the margin between the two candidates is very narrow, as in Florida in 2000, when the election hinged on just 537 votes.

Derek Muller, a law professor at the University of Iowa, said a candidate won't sue if he or she is trailing significantly in a number of states.

"If it comes down to one state," he said, "then I would expect really serious litigation."

But if margins turn out to be two or three percentage points -- say a 100,000 vote difference in Pennsylvania -- "that's pretty difficult to be litigating at the end of the day," said Muller.

"If you have a lawsuit about ... the loss of about 10,000 votes, it's not going to make a difference if the margin ends up being 100,000," said Foley.

Even if asked, the Supreme Court has been cautious over getting involved in voting matters that are decided by state laws.

And, after its decision in 2000 handing the election to Republican George W. Bush left many unanswered questions about Florida's ballot counting, the court is aware that its intervention could damage its own standing in society.

A case would put the political leanings of the nine justices -- six conservatives and three liberals -- in the spotlight.

That light would shine most harshly on the newest member, Amy Coney Barrett, who joined the court only last month, chosen by Trump.

Trump said repeatedly that he rushed her appointment in part so she could be in place to hear any election cases, placing an immediate cloud over her.

"The Supreme Court doesn't have to intervene," said Muller.

"It felt like it needed to in 2000, but it's not necessarily clear they would feel the same way today."