Ariz. Rev. Stat. § 11-441

A. The sheriff shall:

1. Preserve the peace.

2. Arrest and take before the nearest magistrate for examination all persons who attempt to commit or who have committed a public offense.

3. Prevent and suppress all affrays, breaches of the peace, riots and insurrections that may come to the knowledge of the sheriff.

4. Attend all courts, except justice and municipal courts, when an element of danger is anticipated and attendance is requested by the presiding judge and obey lawful orders and directions issued by the judge.

5. Take charge of and keep the county jail, including a county jail under the jurisdiction of a county jail district, and the prisoners in the county jail.

6. Endorse on all process and notices the year, month, day, hour and minute of reception and issue to the person delivering the process or notice, on payment of fees, a certificate showing the names of the parties, the title of the paper and the time of reception.

7. Serve process and notices in the manner prescribed by law and certify under the sheriff's hand on the process or notices the manner and time of service, or if the sheriff fails to make service, the reasons for failure, and return them without delay. When returnable to another county, the sheriff may enclose such process or notices in an envelope, addressed to the officer from whom received, and deposit the envelope postage prepaid in the post office. The return of the sheriff is prima facie evidence of the facts stated in the return.

8. Secure, as soon as possible, the home of a deceased person located outside the boundaries of an incorporated city or town if the sheriff is unable to determine or locate the heirs or executor of the deceased person.

B. The sheriff, in executing the duties prescribed in subsection A, paragraphs 1 through 4 of this section, may command the aid of as many inhabitants of the county as the sheriff deems necessary.

C. The sheriff shall conduct or coordinate within the county search or rescue operations involving the life or health of any person or may assist in such operations in another county at the request of that county's sheriff.  The sheriff may request assistance from any persons or agencies in fulfilling duties under this subsection. A search and rescue unit established or recognized by a county may possess human remains as defined in section 36-301 for the purpose of training canines used for search and rescue work. The sheriff or the sheriff's designee shall keep an inventory of all human remains that are kept for the purpose of training search and rescue canines. The inventory must be updated when the search and rescue unit receives human remains or disposes of human remains that are no longer useful to the search and rescue unit. Each search and rescue unit that possesses human remains for the purpose of training search and rescue canines shall establish policies and standard operating procedures for access to, the inventory of and the possession and disposal of human remains kept for the purpose of training search and rescue canines.

D. The sheriff, in executing the duties prescribed in this section, may request the aid of volunteer posse and reserve organizations located in the county.

E. The sheriff may assist in executing the duties prescribed in this section in another county at the request of that county's sheriff.

F. The sheriff may require any prisoner who is on work release to reimburse the county for reasonable expenses incurred in connection with the release.

G. The board of supervisors of a county bordering Mexico may adopt an ordinance pursuant to chapter 2 of this title allowing the sheriff to prevent the entry from this state into Mexico at the border by any resident of this state who is under eighteen years of age if the minor is unaccompanied by a parent or guardian or does not have written consent for entry from the minor's parent or guardian. The authority of the sheriff is only to prevent entry and not to otherwise detain the minor. This subsection does not limit the authority of the sheriff pursuant to any other law.  A county is not civilly or criminally liable for not adopting an ordinance pursuant to this subsection.

H. Notwithstanding section 13-3112, the sheriff may authorize members of the sheriff's volunteer posse who have received and passed firearms training that is approved by the Arizona peace officer standards and training board to carry a deadly weapon without a permit while on duty.