because congress is granted the authority to create laws

murder is not "legal federally"
in cases where The United States has police power, murder is illegal
i.e. Wash DC, federal land, military bases, etc.

as long as it doesnt break a constitutional right then they can do it

And what part of the Constitution gives them police power?

the federal murder laws do not apply within the territory of any State
unless there is some jurisdictional vector

Is it me, does Markiplier starting to look like a Guru?

https://www.youtube.com/watch?v=X7mM_-Is-W8

FBI is a thing

the Constitutional grants the police power to the States @Bookworm

Then the federal government has no authority to police.

DC

parks, military bases, embassies

etc.

It does, according to the executive branch clause

Do you have a link, Codes?

They may enforce federal law

https://www.fbi.gov/about/faqs/where-is-the-fbis-authority-written-down

is this actually difficult to understand?

does Rhode Island have jursidiction in New York?

of course not

the feds have primary jurisdiction in their own territory

Except the right to police is granted to the states, you said.

yeah

DC is not a state

The FBI does not police people

military bases are not a state

They investigate federal crimes

yes

Define policing

If they investigate and take into custody suspected criminals for prosecution, how is that not policing?

federal crimes are enabled by specific authority
contained in the constitution (Interstate Commerce Clause, for the most part)
or in laws enabled by treaty

"taking into custody" is policing

and the feds do so in cases where they have jurisdiction

murder is a state crime, and does not grant federal jurisdiction

So ultimately there is federal authority to police, but it is limmitted

yes, of course

hence federal prisons holding millions of inmates

or hundreds of thousands, or whatever it is

Feds often work closesly with states either way anyway from what I understand

indeed

The federal government has the right to police their own laws. Remember the FBI was borne of the effort to enforce Prohibition.