I am sorry, but the case details you have provided are insufficient to create a legal summary. The title "Section 18 in The Probation of Offenders Act, 1958" and the court "Union of India - Section" along with the date "16 May 1958" are not enough to identify a specific case. A proper case citation (e.g., case name v. case name, year, court, and report details) is required to locate the relevant judgment and create an accurate summary. Furthermore, "Section 18 in The Probation of Offenders Act, 1958" is a provision of a statute, not a case title.

To provide a useful summary, I need the full case name (e.g., State of Maharashtra v. XYZ), the court that decided the case (e.g., Supreme Court of India, High Court of Bombay), and preferably a citation to the official law reports where the case is published (e.g., AIR 2000 SC 1234).