1. liable to be impeached; subject to formal accusation of misconduct in office
Usage: formal, legal
2. open to question or doubt; questionable in credibility or validity
Usage: formal

Examples

• The president's conduct was considered impeachable by members of Congress.
• An impeachable witness may have a history of dishonesty.
• The evidence presented was impeachable due to procedural errors.
• Officials found the official's actions impeachable under the law.
• His testimony was impeachable because of contradictions in his earlier statements.