Welf. & Inst. Code, § 5358.5

When any conservatee placed into a facility pursuant to this chapter leaves the facility without the approval of the conservator or the person in charge of the facility, or when the conservator appointed pursuant to this chapter deems it necessary to remove his conservatee to the county designated treatment facility, the conservator may take the conservatee into custody and return him to the facility or remove him to the county designated treatment facility. A conservator, at his discretion, may request a peace officer to detain the conservatee and return such person to the facility in which he was placed or to transfer such person to the county designated treatment facility, pursuant to Section 7325 of the Welfare and Institutions Code. Such request shall be in writing and accompanied by a certified copy of the letters of conservatorship showing the person requesting detention and transfer to be the conservator appointed pursuant to this chapter as conservator of the person sought to be detained. Either the conservator or his assistant or deputy may request detention under this section. Whenever possible, persons charged with apprehension of persons pursuant to this section shall dress in plain clothes and shall travel in unmarked vehicles.