The Supreme Court resolved in JARDIN, et. al., vs. NLRC, et. al., G.R. No. 119268, 2000 February 23that for a valid dismissal in labor cases, the existence of just and authorized causes for dismissal must be present plus the twin-notice requirement, to wit:


"As consistently held by this Court, termination of employment must be effected in accordance with law. The just and authorized causes for termination of employment are enumerated under Articles 282, 283 and 284 of the Labor Code. The requirement of notice and hearing is set-out in Article 277 (b) of the said Code. Hence, petitioners, being employees of private respondent, can be dismissed only for just and authorized cause, and after affording them notice and hearing prior to termination. In the instant case, private respondent had no valid cause to terminate the employment of petitioners. Neither were there two (2) written notices sent by private respondent informing each of the petitioners that they had been dismissed from work. These lack of valid cause and failure on the part of private respondent to comply with the twin-notice requirement underscored the illegality surrounding petitioners’ dismissal."