kick over the traces

Fig. to do what one is meant not to do; to rebel against authority. (Alludes to a horse that steps on the wrong side of the straps that link it to whatever it is pulling.) At the age of sixty, Walter kicked over the traces and ran away to Brazil. All these young kids seem to want to kick over the traces.

to do what you want and not show any respect for authority Some kids go straight to university and spend the first year kicking over the traces.

Break loose from restraint, misbehave. For example, There's always one child who'll kick over the traces as soon as the bell rings. This metaphoric expression alludes to the straps attaching a horse to a vehicle, which the animal sometimes gets a leg over in order to kick more freely and thereby refuse to move forward. [Mid-1800s]

To act in a way that contravenes social expectations or propriety: "As soon as the opportunity presented itself, [he] kicked over the traces and threw himself into a life of pleasure" (K.D. Reynolds).

To disregard what is expected and follow your own wishes. Traces are the leather harness straps by which a horse is attached to a wagon or another vehicle. When the animal becomes upset, it may well kick out and end up stepping over the traces. At that point the driver has little or no control in steering or stopping. A person who rebels against convention and acts in what society would consider an unseemly manner has kicked over the traces. A similar equine-derived expression is “spit the bit and chuck the harness.”