Trump impeachment clears first hurdle as US Senate says trial is constitutional

Former US president Donald Trump. Photo / AP

The US Senate has voted 56-44 that it is constitutional to hold a trial for a president who is no longer in office.

That means Donald Trump's second impeachment trial will continue, starting tomorrow.

Only a simple majority was required on the measure.

The vote count was 56-44. That's almost the same as its vote on essentially the same question late last month, when the margin was 55-45. One additional Republican, Senator Bill Cassidy, has chosen to join the Democrats in declaring the trial constitutional since then.

The other five Republicans to favour moving forward were Mitt Romney, Ben Sasse, Susan Collins, Lisa Murkowski and Pat Toomey.

Today's 56-44 vote to declare the trial constitutional is another sign it will end in Trump's acquittal.

Conviction requires 67 votes in the Senate. That means it cannot happen unless 11 Republicans who just voted to say the trial was unconstitutional change their minds a few days from now and vote to convict.

The trial will now adjourn until tomorrow, when it will hear from the Democratic impeachment managers, who will get 16 hours in total to make their case.

The defence will follow later in the week.