The actress led a rally against the proposed TransCanada Corp's Keystone oil pipeline, which will stretch from Canada to Texas.
Kidder, a Montana resident, insisted that the pipeline will cause dangerous oil leakage and urged President Barack Obama to block its construction.
"We're the first state the pipeline goes through. It's bound to leak, there's no way it's not going to... They always assure us these things are safe, and they never are," Kidder told those in attendance.
Moments after addressing the crowd, police arrived and arrested Kidder and Legends of the Fall star Tantoo Cardinal for failing to obey an order governing protests on the sidewalk, according to CBC.
Cardinal and Kidder were released from police custody on Tuesday evening.
Kidder, who played Lois Lane in Superman, has been an active campaigner for the Progressive Democrats of America.
The Canadian-born Kidder became a US citizen in 2004 in order to take a more active role in American politics.
She last appeared on the big screen in Rob Zombie's 2009 horror film Halloween II.
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