Giles received his JD from Arizona State University's Sandra Day O'Connor College of Law in 1987.

[5] Giles was elected to the Mesa City Council in 1996, serving until 2000, including a term as vice mayor from 1998 until 2000.

As Chair of the Maricopa Association of Governments (MAG),[14] Giles started the program in 2021 to help combat homelessness, not just for veterans, but for all of the residents within Mesa.

In 2023, Mesa City Council approved the purchase of a hotel to serve as an emergency shelter facility for the Off the Streets program.

[21] He endorsed Democrat Kamala Harris in the 2024 United States presidential election over Donald Trump, the Republican nominee.

[24] In December 2024, the Mesa City Council voted unanimously to approve an increase in the costs of water, wastewater, and other utilities.

[25][26] In 2022, Giles requested federal funds in order to improve transportation, and the city received a $16 million grant through the Bipartisan Infrastructure Act.

Giles' goal is a 40 percent increase in charging stations for electric vehicles along with expansion of the Tempe street car into Mesa.

[27] The city has adopted a climate action plan with a goal of using 100 percent renewable energy and being carbon neutral by 2050.

[28] Giles supported the renewal of Prop 400, [29] a half a cent transportation tax in Maricopa County.

[33] Giles' most recent electoral victory took place in the 2020 non partisan primary, receiving just over 66% of the votes over opponent Verl Farnsworth.