Arrests outside jurisdiction

Here's a hypothetical:  Can a Newtown Township Police Officer arrest someone in Levittown?  The answer is, like so many legal issues, maybe.  42 Pa. Cons. Stat. § 8953 states that a police officer may not, unless they meet one of the exceptions/conditions outlined in the rule.  The exceptions include:

1. If the officer has a court order from a judge
2. If the officer is in "hot pursuit"
3. If the officer has been requested to aid or assist any local, State or Federal law enforcement officer or park police officer or otherwise has probable cause to believe that the other officer is in need of aid or assistance.
   
4. If the officer the officer has obtained the prior consent of the chief law enforcement officer, or a person authorized by him to give consent
5. If the officer is on "official business"
6. If the officer believes or witnesses a felony

Hot pursuit in Bucks County

The biggest issue I have seen in cases is "hot pursuit".  Hot pursuit, as Commonwealth v. Laird pointed out, "entails some sort of chase, though the chase need not involve a fender smashing Hollywood style chase scene or be newsworthy."   This frequently happens in a DUI case (which is a misdemeanor), where the individual is followed by the police and stopped outside the jurisdiction.  But, at what point does a person know they are being chased?  It certainly is a tough case to argue a person did not know they were being chased if the officer is directly behind them and with their lights on.  But, if no lights are on, you have more of an issue about hot pursuit.