[1] After earning his Ph.D. in astrophysics from Columbia University at the age of 24, Quirk became a postdoctoral fellow at the California Institute of Technology in Pasadena, where he published papers on galactic structure.

Quirk then worked in the computer industry in Silicon Valley before settling into a career at the Lawrence Livermore National Laboratory (LLNL), where he established himself in the fields of atmospheric science and nuclear technology design.

Since being elected to the California State Assembly in November 2012, Quirk has served on five committees: Rules, which determines what committees bills are sent to; Appropriations, which determines whether bills that appropriate funds can proceed to a vote of the full assembly; Utilities and Commerce, that deals with the state's telecommunication, electric, gas, and water utilities; Agriculture; and Public Safety.

In 2016, Quirk authored Assembly Bill 2130 titled "An act to amend Section 281 of the Public Utilities Code, relating to telecommunications," which would freeze the California Advanced Services Fund broadband infrastructure subsidy program and replace it with what amounts to a $100 million no-strings gift from the taxpayers to (mostly) AT&T, according to Steve Blum of Tellus Venture Associates.

[4] In September 2016, the California State University East Bay Educational Foundation of Quick's district was selected as one of 18 recipients nationwide that shared in $10 million from AT&T through the Aspire Connect to Success Competition.

[5] In 2017, Quirk was principal coauthor of the controversial California Senate SB 649[6] which would remove a city's ability to control where 5G technology is placed and transfer that power to the state.

[7] In 2018, Quirk was the sponsor of a bill to allow PG&E to defray the cost of settlements related to their negligence in the October 2017 Northern California Wildfires by forcing ratepayers to pay.