WP:ARBPIA:

1.1) Any uninvolved administrator may, on his or her own discretion, impose sanctions on any editor working in the area of conflict if, despite being warned, that editor repeatedly or seriously fails to adhere to the purpose of Wikipedia, any expected standards of behavior, or any normal editorial process. The sanctions imposed may include blocks of up to one year in length...

2) Discretionary sanctions imposed under the provisions of this decision may be appealed to the imposing administrator, the appropriate administrators' noticeboard (currently WP:AE), or the Committee. Administrators are cautioned not to reverse such sanctions without familiarizing themselves with the full facts of the matter and engaging in extensive discussion and consensus-building at the administrators' noticeboard or another suitable on-wiki venue. The Committee will consider appropriate remedies including suspension or revocation of adminship in the event of violations.

For the avoidance of any doubt, I have copied those sections from the final decision.  Talk