autojustificar

To rationalize or excuse one's own behavior, usually with a critical undertone suggesting the justification is self-serving rather than objectively valid.

• Siempre autojustifica sus errores culpando a los demás. — He always justifies his own mistakes by blaming others.
• Es fácil autojustificarse cuando no queremos admitir una falta. — It's easy to justify yourself when you don't want to admit a fault.
• Dejó de autojustificar cada decisión y empezó a pedir disculpas. — He stopped justifying every decision and started apologizing.

Carries an implicit skepticism that plain justificar doesn't — using it for a legitimate, well-founded explanation can sound like you're implying the person is making excuses.

Often confused with justificar.