What is an 'autopen' and do Trump's claims about Joe Biden's use of it stack up?

 https://www.abc.net.au/news/2025-03-18/what-is-an-autopen-and-trump-claims-examined/105064992

Donald Trump claims Joe Biden's January 6 committee pardons are "void" because the former president signed them using an "autopen".

Presidents — including Trump — have used autopens for decades to sign documents and correspondence.

And one expert says that by raising the issue, Trump is only opening himself up for potential problems down the track.

Trump hasn't offered any evidence to support his claims, and neither has the White House.

When asked whether Trump had legal authority to void pardons signed by autopen, press secretary Karoline Leavitt questioned Biden's awareness of the pardons in the first place.

Dr Melkonian says there is no evidence to support Trump's claims, but if pardons were being signed without Biden's knowledge, it would be "a constitutional failure".

"Trump is really exaggerating the Biden situation," he said.

"The mere fact you disagree with what Joe Biden did does not mean he was mentally incompetent. There’s a big difference."