I know, but really...this isn't the FBI following serial killers around the country (although logically that's what would probably happen). It's so unrealistic for CSIs, or even local cops, to do this.
The other part...I get. About how they are there anyway and the novelty of seeing them in another city. But man...sounds like the whole rest of the season is gonna be a big cluster. Hope it proves otherwise.
Well i'm not too sure how it works in America, but in the Uk if a police force has an interest in another individual currently residing in another police forces jurisdiction then they can request that they be allowed to arrest the individual themselves and collect any evidence.
In this case LV has the most history with Haskell and therefore might be extended the professional courtesy of dealing with Haskell (i.e Sofia invites them onboard to clean up their mess ).
Here's a little quote that might help explain this to those outside the US:
"If the crime happens in one state, it is typically a state crime , unless it is an expressly named federal crime. But if a crime occurs throughout many states, or crosses state lines, it often becomes a federal crime.
The differences between federal and state crimes can be much more complicated. State crimes are typically all conduct that violates state laws, such as murder, traffic violations, and other areas where conduct is completely encompassed in the state. Federal crimes are specifically enumerated federal offenses, such as IRS violations, mail fraud, kidnapping, counterfeiting, damaging or destroying mailboxes, and immigration offenses.
When a crime committed seems that it could be charged as a state crime or a federal crime, the US Constitution’s “Supremacy Clause” states that federal law will trump state law, and the federal authorities will take the case over."
In the case of Haskell, he fled over state lines and appears to be holding one of his "brides" as hostage. Since he escaped a Nevada prison and is now a kidnapper (a federal crime) in California, that makes his crimes interstate - thus the jurisdiction of the Feds and the FBI. So basically, LVPD would have little jurisidiction over this case. It would be up to the Feds to decide how much they can assist in it.
Oh, and it should be noted that generally States act independently of each other and may not feel open to working alongside another's law enforcement. It depends on the variables of the case...