&gt; Ten days later, a Mountain View motorcycle cop noticed traffic stacking up behind a Google car going 24 miles an hour in a busy 35 mph zone. He zoomed over and became the first officer to stop a robot car. He didn’t issue a ticket -- who would he give it to? -- but he warned the two engineers on board about creating a hazard.<p>&gt; “The right thing would have been for this car to pull over, let the traffic go and then pull back on the roadway,” said Sergeant Saul Jaeger, head of the police department’s traffic-enforcement unit. “I like it when people err on the side of caution. But can something be too cautious? Yeah.”<p>I believe that this reflects the 25 mph maximum speed that Google has set. I don&#x27;t know CA law, but in some places it&#x27;s illegal to go under 25 mph in a 35 mph zone. It&#x27;s always safest to minimize speed difference with other vehicles. Even if that means exceeding the limit. That won&#x27;t protect against citations in speed traps, however.