What is necessary to establish "opportunity" in the context of deadly force?

To establish "opportunity" in the context of deadly force, it is essential that the suspect is physically close enough to pose a threat. This physical proximity creates a situation where the officer can reasonably determine that their life or the lives of others are in immediate danger due to the suspect's potential actions. The concept of opportunity hinges on the capability of the threat to materialize; therefore, if the suspect is not within a viable distance to inflict harm, the justification for using deadly force weakens significantly.

The other options focus on different aspects of a situation but do not directly address the immediate threat presented by the suspect. For instance, availability of backup might influence an officer's decision-making process but doesn't define the suspect's ability to pose a lethal threat at that moment. Similarly, the public nature of a crime or the presence of a witness can affect the overall circumstances surrounding a police encounter but are not directly related to establishing an imminent threat through opportunity.