I believe that your interpretation is wrong. He was charged, convicted AND impeached by Congress. The Senate voted to not remove him from office. It does not necessarily require that an actual law was broken. It is the sole right of Congress to decide what impropriety is considered impeachable.
I think your interpretation might be wrong because the word conviction does not happen until it is sent to the Senate for trial. Also Congress is the term for both the house of rep and the senate. He was impeached in the house and went to trial in the Senate. I know that it is nitpicking but thought you would appreciate it.
Article One of the United States Constitution gives the
House of Representatives the sole power of impeachment and the Senate the sole power to try impeachments of
officers of the U.S. federal government. (Various
state constitutions include similar measures, allowing the
state legislature to impeach the
governor or other officials of the state government.) In the United States, impeachment is only the first of two stages, and conviction during the second stage requires "the concurrence of two thirds of the members present".
[34] Impeachment does not necessarily result in removal from office; it is only a legal statement of charges, parallel to an
indictment in
criminal law. An official who is impeached faces a second legislative vote (whether by the same body or another), which determines conviction, or failure to convict, on the charges embodied by the impeachment. Most constitutions require a
supermajority to convict. Even if the subject of the charge is criminal action, it does not constitute a criminal trial; the only question under consideration is the removal of the individual from office, and the possibilities of a subsequent vote preventing the removed official from ever again holding political office in the jurisdiction where they were removed.