https://www.lexology.com/library/detail.aspx?g=596b7bb8-8d14...
Legislative framework

Relevant legislation
What is the relevant legislation regulating the award of public contracts?

The main legislation is Law 22 of 2006, which regulates public procurement (the Public Procurement Law), as amended by Law 61 of 2017. Further regulation of Law 22 of 2006 was implemented by Executive Decree 366 of 2006.

Additional legislation of relevance includes:

Executive Decree 188 of 2009, which regulates contractor selection procedures through PanamaCompra, Panama’s electronic public procurement system;
Law 38 of 2000, which establishes the framework for administrative proceedings;
***Law 48 of 2016, which establishes retaliatory measures for countries discriminating against the Republic of Panama;***
Law 16 of 1992, which establishes privatisation proceedings; and
Law 1 of 2001, which regulates the acquisition of medicines, supplies and medical equipment, by the Social Security Administration.

Public Procurement Law specifically states that the following principles shall govern public tenders: equal treatment, transparency and competition, among others previously stated.

[...]

The Public Procurement Law states that public servants may not celebrate, by themselves or through interposed persons, contracts with the entity in which they work, or participate in as owners, partners or shareholders of the company or as administrators, managers, directors or legal representatives of the bidder in a public tender.


https://www.centralamericadata.com/en/article/home/Panama_Ch...
Panama: Changes to Law on Public Procurement
In addition to forbidding the participation of companies whose representatives have committed crimes against the public administration, a proposal has been made to eliminate hidden costs in tenders and modify the advance payment bonds to the companies awarded contracts.

The bill amending the Public Procurement Law 22 was prepared by the Ministry of Economy and will be presented to the Cabinet on 19 January, and then submitted for discussion to the National Assembly. One of the new features in it is the elimination of the hidden prices in tenders for best value with separate evaluation.

See also: "Panama: Convicts May Sell to the State"

With regard to the advance payment bonds, "... it is established that this mechanism" guarantees reimbursement of a certain sum of money paid as an advance to the contractor .'" Prensa.com reports that "...This deposit, will in no case be less than 100% of the amount advanced, and will be valid for the main period and an additional period of 30 subsequent calendar days until its maturity. It is also indicated that in no case may the contracting state entity make advance payments exceeding 20% ​​of the total contracted amount. "

See previous entry. I think either public session / public ceremony would work here, though you would probably need to add "specified / announced in"
https://www.proz.com/kudoz/spanish-to-english/law-contracts/...

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Note added at 2 hrs (2022-11-21 14:49:33 GMT)
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@Phil: Yes, I'm aware it doesn't say "specified in" - it says "del", and you could say "of the" in the English no problem (in the sense of "belonging to"). I just think "specified in" makes it clearer and sounds more natural in English.

Procedimiento administrativo por el cual el Estado, previa convocatoria pública, selecciona entre varios proponentes, ya sean personas naturales o jurídicas y en igualdad de oportunidades, la propuesta o las propuestas que reúnen los requisitos que señalan esta Ley, los reglamentos y el pliego de cargos.

Artículo 2, Ley 22 de 27 de junio de 2006