G.R. No. L-26815 - Santos vs. Sibug

On July 21, 1987, the Republic of the Philippines, through the Presidential Commission on Good Government (PCGG), filed a Complaint for Reconveyance, Reversion, Accounting, Restitution and Damages against Bienvenido R. Tantoco, Sr. and Jr., Gliceria R. Tantoco, Maria Lourdes Tantoco-Pineda, Dominador R. Santiago, Ferdinand E. Marcos (substituted by his heirs Imelda, Ferdinand R. Jr., Imee, Irene) and Imelda R. Marcos, alleging the accumulation of ill-gotten wealth.
The PCGG alleged that former President Marcos unlawfully withdrew funds from the National Treasury and Central Bank and transferred them through payees; that the Tantocos and Santiago acted as dummies/nominees; that The Duty-Free Shops (TDFS) diverted 5% of franchise taxes to private foundations; and that respondents obtained unwarranted tax-free import privileges and a 25-year franchise under PD 1193.

Substitutions: following the deaths of Ferdinand E. Marcos and Gliceria R. Tantoco, they were substituted by their heirs and by Santiago (as executor), respectively.
Discovery proceedings (1989–1993): respondents served interrogatories and requests for production; the Sandiganbayan granted motions and PCGG produced Exhibits A–LLL, then repeatedly manifested no more documents but subsequently offered Exhibits MMM–QQQ-5, RRR–YYY and AAAAAAA-105 during pretrial and trial. Respondents’ motions to exclude these exhibits were denied.
Admissibility rulings: on January 15, 2008, the Sandiganbayan denied all exhibits for violating the Best Evidence Rule; on September 25, 2008, it admitted only Exhibits FF, GG, GG-1, HH, HH-1, XX, YY, ZZ, AAA, BBB, CCC and MMM–AAAAAAA; on June 3, 2009, it rescinded admission of MMM–AAAAAAA; the Supreme Court, in G.R. No. 188881 (Apr. 21, 2014), affirmed exclusion of MMM–AAAAAAA and upheld admission of the 11 exhibits.
Dismissal and appeal: on September 25, 2019, the Sandiganbayan dismissed the Expanded Complaint for insufficiency of evidence; on November 20, 2019, it denied reconsideration; the Republic and PCGG filed a Rule 45 petition in the Supreme Court (G.R. No. 250565), which was resolved on March 29, 2023.

Did the Sandiganbayan err in excluding the bulk of PCGG’s documentary exhibits for failure to disclose them during discovery and for violating the Best Evidence Rule?
Were the remaining 11 exhibits and the testimonies of four witnesses sufficient, by a preponderance of evidence, to prove the allegations of ill-gotten wealth and respondent-as-dummy conduct?