Did Scalia Have a Liberal Side?

No, but the Justice had a libertarian side that occasionally created shared space with liberal justices. Consider Von Raab v. National Treasury Employees Union,  a broadly worded opinion that approved a drug testing program for customs agents, even though there was no evidence that drug use was an issue with these employees. The decision is the leading precedent for today's drug-testing in the workplace-- testing that sometimes is overbroad and unrelated to an employer's legitimate interests.

Here is an excerpt of his dissenting opinion, joined by a liberal Justice, John Paul Stevens:

Until today this Court had upheld a bodily search separate from arrest and without individualized suspicion of wrong-doing only with respect to prison inmates, relying upon the uniquely dangerous nature of that environment. Today, in Skinner, we allow a less intrusive bodily search of railroad employees involved in train accidents. I joined the Court's opinion there because the demonstrated frequency of drug and alcohol use by the targeted class of employees, and the demonstrated connection between such use and grave harm, rendered the search a reasonable means of protecting society. [489 U.S. 656, 681].  I decline to join the Court's opinion in the present case because neither frequency of use nor connection to harm is demonstrated or even likely. In my view the Customs Service rules are a kind of immolation of privacy and human dignity in symbolic opposition to drug use.