If we live on Mars someday,how will people on earth control people on Mars as far as laws?

The same way the British empire controls the United States.

It will be another US and Russian territory for a while and slowly become it's own countries.
Maybe even Chinese territory.

The laws will be adopted from the countries on earth and later modified to its own independence.

... Theill be marsian police duhh

No need. It is called good riddance. The travel pattern is no t something like Europe to USA. It takes a life-time to settle down.

We have more uranium and plutonium on Earth than Mars possesses....

I think that's 'nuff said. So... you just *watch it*, Martians....

Our law are doing rather poorly with Earth people; hopefully people on Mars will govern themselves.