Final answer:
Generally, one should not pass cars that have pulled over for emergency vehicles without ensuring it is safe and legal to do so. Rule Utilitarianism might justify breaking a rule in exceptional circumstances, but traffic laws should be observed carefully.
Step-by-step explanation:
Whether it is acceptable to pass cars that have pulled over for emergency vehicles depends on the context and local laws. Generally, exercising caution and complying with traffic laws is essential.
In most cases, when vehicles have pulled over to allow emergency vehicles to pass, it's important to follow traffic laws carefully. According to the principle of Rule Utilitarianism (RU), one should follow rules that generally promote the greatest good for the greatest number, such as stopping at red lights. However, there may be exceptional circumstances, like in the scenario where a pregnant woman is about to give birth, where breaking a traffic rule at a specific time (like 4 AM with no other cars around) could potentially lead to a greater overall utility.
Nevertheless, in usual circumstances, after emergency vehicles have passed, drivers should proceed with caution, and only when it's safe to do so. One must not automatically assume that it is always 'okay' to pass vehicles that have pulled over for emergency vehicles without assessing the safety and legality of the situation first.