Knopp served three terms in the Oregon House of Representatives. He was first elected in 1998 and left the House in 2005. Knopp was majority leader in 2003. In 1999, Knopp helped enshrine Oregon's unique "kicker" law, which returns excess tax revenue back to taxpayers, into the Constitution by sponsoring referral legislation that brought Measure 86 to the voters in 2000. Measure 86 was approved by a 62% of voters.
Oregon Senate
Knopp was first elected to the Oregon Senate in 2012. At the time, Knopp was executive vice president of the Central Oregon Home Builders and a past president of the Deschutes CountyRepublicanCentral Committee. He defeated incumbent Senator Chris Telfer in the Republican primary, winning 38% of the primary vote to Telfer's 32%. Knopp then defeated Democratic nominee Geri Hauser in the general election. In 2014, Knopp was named deputy caucus leader of the Oregon Senate Republicans. Knopp won reelection in 2016 with 60.9% of the vote, defeating Democratic nominee Greg Delgado. Considered a voice of bipartisanship in the Oregon Senate, Knopp has led efforts aimed at addressing workplace sexual harassment, public pension reform, equal pay, and paid family and medical leave. Knopp opposed the 2019 cap and trade bill that was reported to increase the cost of living on large portions of his constituency. In 2019, Knopp and the other 11 state Senate Republicans walked out of the state Senate session, seeking to block the passage of the bill in a session of Democratic supermajority. Most Republicans fled to Idaho, depriving the chamber of a quorum. Republicans maintained that the bill would do nothing to stop climate change and dramtacally increase costs of living in Oregon. In an interview with The Oregonian Knopp said, "I feel no constitutional obligation to stand around so they can pass their leftist progressive agenda... I think that’s true for every other Senate district that's out there that's represented by Republicans." Knopp was an opponent of legislation in 2015 and 2019 to eliminate non-medical exemptions to the requirement that Oregon schoolchildren be vaccinated. While speaking against the bill at a rally in 2019, Knopp said passage of the legislation would lead to "no freedom in America."
Personal life
Knopp is married to his wife, Melissa and has four children.