Can a witness who refuses to testify be considered unavailable?

In People v. Rojas, supra, 15 Cal.3d 540, 125 Cal.Rptr. 357, 542 P.2d 229, this court held a witness who was physically and mentally able to testify, but who simply refused to do so out of fear for himself and his family, was unavailable within the meaning of Evidence Code section 240, subdivision (a)(3). We explained that "[t]he maxim expressio unius est exclusio alterius is inapplicable ... 'where no reason exists why persons and things other than those enumerated should not be included, and manifest injustice would follow by not including them....' [p] Section 240 clearly expresses a legislative intent to deem a person 'unavailable as a witness' in specific cases which were recognized under existing law. [Citation.] No [ ] sufficient reason appears to us why the former testimony of a witness who is present in court but refuses to testify because he is in fear of his safety or that of his family should not be used when that of a witness, who claims privilege or who is absent from the hearing and his attendance cannot be compelled or procured, can be used." (Id. at p. 551, 125 Cal.Rptr. 357, 542 P.2d 229, fn. omitted; accord, People v. Francis (1988) 200 Cal.App.3d 579, 587, 245 Cal.Rptr. 923 [Witness who refuses to testify is unavailable "even though such a witness does not fit neatly into one of the subdivisions of Evidence Code section 240." (Italics added.) ].)