Arnie is a former high school principal and math teacher. He was a Democratic politician who served as a member of the Oregon House of Representatives from the 9th district, which spans the southern Oregon Coast. He also served as co-speaker of the House for the 2011–2012 session along with Republican Bruce Hanna. He served as a member of the Oregon State Senate from 2013 to 2021.

As an educator and principal, he created numerous opportunities for students to pursue their interests and develop their talents. He helped develop The Coos Natural Resources course which allows students to explore issues that affect the Coos Bay area, including fisheries management, forestry, water treatment and wildlife management. He has also transformed a radio station that was donated to the school into a student-run, school-to-work program through which students acquire skills in areas ranging from broadcasting and technology to sales. Additionally, Mr. Roblan established a foreign exchange partnership with a school in Hanover, Germany, to allow students from the rural Coos Bay area to experience a new culture first-hand.

He has lived in Coos Bay since the early-1970s with his wife Arlene. They have three children.