Alberta Government House Leader Jason Nixon says he doubts controversial legislation proposed a party leadership candidate would even pass in the legislature.

Nixon says the Alberta sovereignty act proposed by Danielle Smith would not only be illegal, it would be bad for business and politically catastrophic because it vastly overpromises what it can't deliver.

Smith is one of the front-runners in the race to replace Jason Kenney as party leader and premier in October.

She has promised that if she wins, she would bring in this fall a bill granting Alberta the power to refuse to enforce federal laws or court decisions it deems an intrusion on provincial rights or a threat to Alberta interests.

Nixon said Premier Jason Kenney’s government has fought — and will continue to fight — for a better deal with the federal government through such measures as building consensus and using court challenges.

Smith, responding in a statement, said “Minister Nixon is incorrect.” She added that the sovereignty act would only be invoked on a case-by-case basis and only after gaining support of members in the house in a free vote each time.