Rosen represented District 24 in the Senate from 2003 to 2013. She was redistricted to District 23 in 2012. Her service earned her the "Freshman Legislator of the Year" award. As a freshman senator, Rosen earned the distinction of being a leading authority on methamphetamine and other drug-related issues. She organized the Minnesota Meth Task Force and, under her direction and leadership, developed and passed the groundbreaking Minnesota Meth bill in 2005. This law is the most aggressive and comprehensive meth legislation in the nation. She continues to work passionately towards fighting drug use among children and adults. Along with her work on drug and public safety issues, former Governor Tim Pawlenty called Rosen a "strong voice for rural Minnesota." She has a background in agriculture. She is also active in seeking improvements in health care, working towards finding a more affordable and beneficial cost and delivery program that supplies the people of Minnesota with better health care benefits. In November 2008, she was appointed by Pawlenty to the Rural Health Advisory Committee. The Rural Health Advisory Committee advises the Minnesota Commissioner of Health and other state agencies on rural health issues. It consists of 15 members appointed by the Governor. Rosen consistently voted against the legalization of same-sex marriage. In 2006, she voted to force a Minnesota marriage amendment out of committee and onto the floor. In 2011, Rosen voted to place a same-sex marriage ban question on Minnesota's 2012 ballot. She voted against the 2013 bill to legalize same-sex marriage in Minnesota. In 2008, Rosen voted against a bill that would have allowed local governments to offer whatever health benefits they chose, including domestic partner benefits, to their employees. In 2009, Rosen voted against school anti-bullying legislation that would protect LGBTQ youth. She voted for the Limmer Amendment to SF 971, which specifies that the bill does not imply that Minnesota condones homosexuality or bisexuality, nor that education institutions are permitted to promote homosexuality or bisexuality or require them to be taught as "acceptable lifestyles." In 2009 and 2010, Rosen voted against a bill that would provide death rights to domestic partners. Following her re-election in 2012, Rosen was mentioned as a potential candidate for Senator or Governor of Minnesota.
She was married to Tom Rosen until 2010. He is the CEO of Rosen's Diversified, Inc., a Fairmont company that specializes in beef processing and agricultural chemical distribution and fertilizers. They are the parents of three children. In 2005, she was honored as the first female to receive the Alumni of the Year award from the College of Agricultural Sciences at Colorado State University.
