Ms Hemphill told Sky News she didn't realise at the time she was part of a "cult" and that Mr Trump had put out the "big lie that the election was stolen".
A former Trump supporter jailed over the US Capitol riots has said she's rejected the president's pardon after seeing through the "MAGA cult".
Mr Trump has pardoned about 1,500 supporters charged over the violence on 6 January 2021, which saw people storm the Capitol building in Washington to try to stop Joe Biden's victory being signed off.
Pamela Hemphill told Sky's The News Hour with Mark Austin it would be a "slap in the face to the rule of law, the Capitol police officers and to our nation".
President Trump told reporters on Wednesday the rioters had "already served years in prison" and had been treated harshly compared with other groups.
