When can express actual authority be invalidated?

Express actual authority can be invalidated when it is given under fraudulent circumstances because the fundamental principle of forming a valid agency relationship is that both the principal and the agent must engage in the agreement in good faith and with honesty. If the authority is granted based on deception or misleading information, then the legitimacy of that authority is compromised. The principal's consent to the agency relationship must be genuine, and if fraud is involved, the express authority cannot stand as it lacks a necessary element of trust inherent in the agency relationship.

The other circumstances mentioned do not inherently invalidate express actual authority. For instance, an agent's ability to act may be limited if the principal is incapacitated, but that does not retroactively invalidate the authority granted before the incapacity occurred. Similarly, the agent acting in an emergency does not negate the authority but instead may create an implied authority to act in urgent situations. Lastly, while there may be a tension between express and implied authority, any conflict does not invalidate the express authority; it simply guides the scope within which the agent can operate. Therefore, the invalidation of express actual authority specifically arises when it is granted under fraudulent circumstances.