Justice Department attorneys are advancing an argument at the Supreme Court that could allow the government to invoke international treaties as a legal basis for policies such as gun control that conflict with the U.S. Constitution, according to Sen. Ted Cruz, R-Texas.

Their argument is that a law implementing an international treaty signed by the U.S. allows the federal government to prosecute a criminal case that would normally be handled by state or local authorities.

That is a dangerous argument, according to Cruz.

"The Constitution created a limited federal government with only specific enumerated powers," Cruz told the Washington Examiner prior to giving a speech on the issue today at the Heritage Foundation.

"The Supreme Court should not interpret the treaty power in a manner that undermines this bedrock protection of individual liberty,” Cruz said.

In his speech, Cruz said the Justice Department is arguing "an absurd proposition" that "could be used as a backdoor way to undermine" Second Amendment rights, among other things.

The underlying case, Bond v. United States, involves a woman charged with violating the international ban on chemical weapons because she used toxic chemicals to harass a former friend who had an affair with her husband.

Under the Constitution, such an offense would be handled at the state level. In Bond's case, the federal government prosecuted her under the Chemical Weapons Convention Implementation Act.

That law implements the Chemical Weapons Convention, the international treaty Syrian dictator Bashar Assad is accused of violating in that country's vicious civil war.

"The problem here is precisely that Congress, rather than implementing the treaty consistent with our constitutional system of federalism, enacted a statute that, if construed to apply to petitioner’s conduct, would violate basic structural guarantees and exceed Congress's enumerated powers," according to Bond's lawyers.

The Judicial Crisis Network's Carrie Severino said the Bond case could have ramifications for many other issues.

"If the administration is right, the treaty power could become a backdoor way for the federal government to do everything from abolishing the death penalty nationwide, to outlawing homeschooling, to dramatically curtailing the states' rights to regulate abortion," she told the Washington Examiner.

The Judicial Crisis Network is a conservative legal activist group.