Is there a translation for “He thumbed his nose at them”?

Question

In English if you "thumb your nose at someone" you are ignoring their authority..

Is there an expression in Spanish that conveys that same sort of disrespect?

Edit: adding example.

Many pedestrians thumb their noses at traffic rules and instead cross the street without waiting for the green light.

Answer 1

Several expressions can be used:

• Les volteo la cara.
• Le importo un comino.
• Le importa un bledo.
• Le vale madre.
• Se lo pasa por el arco del triunfo.

Examples:

A muchos peatones les importan un bledo las normas de trafico y cruzan la calle sin esperar a que se ponga en verde.

A muchos peatones les valen madre las normas de trafico y cruzan la calle sin esperar a que se ponga en verde.

A muchos peatones le voltean la cara las normas de trafico y cruzan la calle sin esperar a que se ponga en verde.

Muchos peatones se pasan por el arco del triunfo las normas de trafico y cruzan la calle sin esperar a que se ponga en verde.

Answer 2

In this case, I would translate it as:

Muchos peatones pasan de las normas de tráfico y cruzan la calle sin esperar a que se ponga en verde.

Answer 3

For ignoring someone's authority without disrespecting him actively:

• Jaime se hizo el tonto ante la llamada de atención de su profesor.

For doing it with some sort of response or gesture, I'd say:

• Jaime se limitó a mofarse ante el profesor.
• Respondió con una burla.

These phrases are universal Spanish, but won't match as well with your example as more idiomatic, colloquial expressions, which acceptance will depend on the region.

Answer 4

Hay muchas personas que tiran el leon a las reglas del trafico. The idiom "tira el leon" means throwing the lion, meaning showing brazen disregard in the most extreme disrespectful sense of the word. Somewhat like throwing caution to the wind but in the spirit of flipping off another driver who honks at you for cutting in front of them in traffic, and doing it with total disdain.