The cops are technically supposed to have a dB meter to measure anything they think may be above 95 dB.
Modifying an exhaust after the catalytic converter is not illegal as long as it isn't above 95 dB. That is state regulation. It outweighs any municipal code.
If you feel the need to, contact the SEMA action network.
www.semasan.org They represent the interest of motor vehicle enthusiasts at the state and national level. They may be able to tell you how to proceed.
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