California Code, Penal Code - PEN § 669

(a) When a person is convicted of two or more crimes, whether in the same proceeding or court or in different proceedings or courts, and whether by judgment rendered by the same judge or by different judges, the second or other subsequent judgment upon which sentence is ordered to be executed shall direct whether the terms of imprisonment or any of them to which he or she is sentenced shall run concurrently or consecutively. Life sentences, whether with or without the possibility of parole, may be imposed to run consecutively with one another, with any term imposed for applicable enhancements, or with any other term of imprisonment for a felony conviction. Whenever a person is committed to prison on a life sentence which is ordered to run consecutive to any determinate term of imprisonment, the determinate term of imprisonment shall be served first and no part thereof shall be credited toward the person's eligibility for parole as calculated pursuant to Section 3046 or pursuant to any other section of law that establishes a minimum period of confinement under the life sentence before eligibility for parole.

(b) In the event that the court at the time of pronouncing the second or other judgment upon that person had no knowledge of a prior existing judgment or judgments, or having knowledge, fails to determine how the terms of imprisonment shall run in relation to each other, then, upon that failure to determine, or upon that prior judgment or judgments being brought to the attention of the court at any time prior to the expiration of 60 days from and after the actual commencement of imprisonment upon the second or other subsequent judgments, the court shall, in the absence of the defendant and within 60 days of the notice, determine how the term of imprisonment upon the second or other subsequent judgment shall run with reference to the prior incompleted term or terms of imprisonment. Upon the failure of the court to determine how the terms of imprisonment on the second or subsequent judgment shall run, the term of imprisonment on the second or subsequent judgment shall run concurrently.

(c) The Department of Corrections and Rehabilitation shall advise the court pronouncing the second or other subsequent judgment of the existence of all prior judgments against the defendant, the terms of imprisonment of which have not been completely served.

(d) When a court imposes a concurrent term of imprisonment and imprisonment for one of the crimes is required to be served in the state prison, the term for all crimes shall be served in the state prison, even if the term for any other offense specifies imprisonment in a county jail pursuant to subdivision (h) of Section 1170.