Final answer:
To convict an official in an impeachment trial, two-thirds of the Senate must vote for conviction, resulting in removal from office and disqualification from future public offices.
Step-by-step explanation:
For an official to be convicted in an impeachment trial, it requires a two-thirds vote of the Senate. This rule is according to the United States Constitution. Once the House of Representatives votes to impeach an official, the Senate holds a trial. If a two-thirds majority of the senators present at the trial vote to convict, the official is removed from office. A conviction in the Senate does not impose criminal penalties but does disqualify the person from holding future public office.