1) Liable to be impeached 2) Like high-level treason 
• (a.) That may be impeached; liable to impeachment; chargeable with a crime.
Im·peach'a·ble adjective That may be impeached; liable to impeachment; chargeable with a crime. « Owners of lands in fee simple are not impeachable for waste.» Z. Swift. 
impeachable 1. Capable of being impeached: venal, impeachable public servants. 2. Being such as to warrant impeachment: an impeachable offense. 3. Liable to accusation; chargeable with a crime; accusable; censurable.
making one subject to impeachment, as misconduct in office. · liable to be impeached.