What happens when State Regulations impinge on interstate commerce??????

Answer 1

Most of the time, the regulations are invalid pursuant to the Commerce Clause of the constitution.

However, such regulations will be valid if (1) they do not discriminate against interstate commerce, and (2) they do not impose an unreasonable burden on interstate commerce.

Go to this site, and read the cases Bibb v. Navajo Freight Lines and Minnesota v. Clover Leaf Creamery for two good examples of how the supreme court applies the commerce clause.

http://www.law.cornell.edu/supct/cases/topics/tog_commerce_clause.html

Answer 2

State's Rights prevail.