https://www.ibc-madeira.com/images/pdf_PT/pt-05-DL_96_89.pdf

https://dre.pt/application/file/a/115526586

https://dre.pt/application/file/a/105714586

Decree-Law No. 265/72, 31 of July – general rules of captaincies

It establishes the national vessel classification based on (i) the activities to be performed, (ii) the area to be navigated, and (iii) nature of the transport to be carried out, as well as rules on vessels acquisition, construction, and modification. However, it does not provide a definition of the ship or vessel.  This legal framework does not refer to unmanned vehicles but it can be argued that they fall within the category of small crafts carried on board, and as such, exempt from registration but subject to licensing by the Maritime Authority.

Regulation (Portaria) No. 394/2012, of 29 November -   establishes the nuclear structure of the General Directorate of Natural Resources, Maritime Services and Safety

http://www.pgdlisboa.pt/leis/lei_mostra_articulado.php?nid=775&tabela=leis

The CPC establishes, among others, evidence that can be used in civil procedures. The evidence collected by unmanned maritime vehicles, like videos, photos or sounds records shall be admitted in the category of documentary evidence and submitted with the memorials. The party that presents the evidence shall provide to the tribunal and to the other party with the device from where the reproduction of the evidence can be made.

The CC establishes that photographic or cinematographic reproductions of phonographic records and, in general,  any other mechanical reproductions of facts or things that are presented in civil procedures, make full proof of the facts or things they represent unless their accuracy is challenged by the party against whom they are presented. It is argued that this value shall also be given to evidence collected by unmanned vessels since the law does not impose restrictions or any additional requirement regarding the devices used for its collection.

The CPP establishes, among others, evidence that can be used in criminal procedures as well as the value of such evidence. The CPP is more restrictive than the CPC and only admits evidence that is not prohibited by law. Evidence collected by unmanned maritime vehicles can be submitted in the category of documentary evidence, but its admissibility in a concrete case depends on whether the evidence is a video or a photo or a sound recorded. In principle, videos and photos are allowed to be used even when their capture was not previously authorized. In contrast, submission of sound records captured by unmanned maritime vehicles is subject to the legal regime of wiretapping, which is only allowed for  certain crimes and upon the existence of a previous authorization.

The Decree-Law No. 287/87, of 7 July –  defines the legal framework that regulates fishing and marine cultures in waters under Portuguese sovereignty and jurisdiction (internal waters, territorial sea, exclusive economic zone and the sedentary species of the continental shelf*)

* There is only one continental shelf, which includes the areas beyond 200 nautical miles, as reinforced in the decision of the International Tribunal for the Law of the Sea concerning the delimitation of the maritime boundary between Bangladesh and Myanmar in the bay of Bengal

Decree-Law No. 52/85, 1 of March * - defines, among others, the legal regime and procedures for marine scientific research in areas under national sovereignty or jurisdiction (including the continental shelf beyond 200 nautical miles)

* The dispositions of this Decree-law regarding marine scientific research remain in force despite the fact that those applicable to fisheries have been repealed.

It regulates the legal regime for marine scientific research in areas under national sovereignty or jurisdiction (including the continental shelf beyond 200 nautical miles). However, it does not have any information regarding equipment used for marine scientific research purposes, as it may be the case of unmanned maritime vehicles. It  imposes that the marine scientific research project shall use appropriate methods of research, but it does not provide any clarification on what these methods are. It is arguable that the utilization of unmanned maritime vehicles is an appropriate method, provided that its use do not collide with other legitimate uses of the sea.

This legal instrument also imposes that information on the methods and equipment to be used in the marine research project, notably unmanned maritime vehicles, shall be mentioned in the research document as well as imposes an obligation of removal once the project is completed.

It sets forth the legal regime that applies for the emission of the authorization for the private use of the national maritime space for marine scientific research projects. It imposes that the document describing the project shall contain, among others, a detailed description of the processes and equipment to be used in the research. So, any application for authorization for the private use of the national maritime space that employs unmanned maritime vehicles shall have such information in the document that describes the project. The effective use of unmanned vehicles in a marine scientific research project shall observe signaling and safety measures established in the project document and it shall comply with the duty to maintain the good environmental status of the marine environment, as well as the obligation to adopt the necessary measures to reconstruct it, in case it has been affected.

This legal regime is only applicable when the marine scientific research project requires the private use of a national maritime space, that is, when the maritime area where the project is going to be carried out cannot be used for any other purpose (reservation of an area or volume). In other cases, when the project can be implemented without private use, these legal impositions do not apply.

It establishes the strict liability regime that is likely to apply to damages caused to the marine environment by unmanned maritime vehicles used in marine scientific research projects.  In accordance with this regime, the entity in charge of the project will be liable for damages caused by the operator of the unmanned maritime vehicles, if cumulatively, the damage is caused within the scope of the research project, the operator acts in conformity with the guidelines given by the entity in charge of the project, and in case the operator is herself or himself also liable, within the fault-based liability regime.

Resolution of the Assembly of the Republic No. 60-B/97, 14 of October – approves in order to ratify, the United Nations Convention on the Law of the Sea and the Agreement Concerning the Implementation of Part XI of the Convention

When referring to the enforcement powers of the Portuguese authorities in different maritime zones, the law mentions the right of visit* not only to be performed against vessels but also against other floating devices. However, the law does not define what are floating devices.

https://www.azores.gov.pt/NR/rdonlyres/
08A0FC8F-7FDC-46AA-A53F-
7F168690FA63/0/EstatutoPol%C3%ADticoAdministrativoda
RegiãoAutónomadosAçores_PT.pdf

It defines norms that grant the Autonomous Region of Azores powers to legislate in matters that may be related to the use of unmanned maritime vessels and vehicles. In the fisheries sector, the Region can impose specific conditions for the use of unmanned maritime vehicles and vessels in the internal waters and in the territorial sea adjacent to its coast, and also regarding registration of vessels in the Region. In land, aerial and maritime transportation, the Region also has powers that may be extended to unmanned maritime vessels and vehicles. The Region also has the competence to regulate research and technological innovation, which can include unmanned maritime vehicles. In terms of public safety and civil protection, notably regarding oceanography, monitoring and surveillance the Region can also adopt legislation, including matters on unmanned maritime vehicles. 

It defines norms that grant the Autonomous Region of Madeira the power to legislate in matters that may be related to the use of unmanned maritime vessels and vehicles. The Region has general powers to legislate in the fisheries sector, and it may introduce regulations regarding the use of unmanned maritime vehicles and vessels. The Statute also determines the competence of the Region regarding maritime infrastructures and transports, so the Region can regulate the use of unmanned maritime vehicles and vessels if they are used as means of transport. The Region has the competence to legislate in the area of construction, installation, and use of infrastructures for marine scientific research purpose, which can include equipment, notably unmanned maritime vehicles.

International Convention for the Unification of Certain Rules Concerning the Immunity of State-Owned Vessels, 1926

http://treaties.fco.gov.uk/docs/pdf/1980/TS0015.pdf

Adopted 10, April 1926, Brussels

Date of entry into force: 8 January 1937

Date of entry into force in Portugal: 27 December 1938

Convention on the International Maritime Organization

https://treaties.un.org/pages/ViewDetails.aspx?src=TREATY&mtdsg_no=XII-1&chapter=12&lang=en.

Adopted 6, March 1948, Geneva

Date of entry into force: 17 March 1958

Date of entry into force in Portugal: 17 March 1976

Chicago Convention on International Civil Aviation, 1948

https://www.icao.int/publications/Documents/7300_cons.pdf

Adopted 7, December 1944, Chicago

Date of entry into force: 4, April 1947

Date of entry into force in Portugal: 4, April 1947

It establishes the rules regarding civil aviation. The Convention has a rule that specifically regulates unmanned aircraft, which can only fly the territory of a State with prior authorisation and in accordance with the conditions established by the State. It also determines that each State undertakes to ensure that the flight of unmanned aircraft in regions open to civil aviation shall be so controlled as to obviate danger.

International Regulations for Preventing Collision at Sea (COLREGS Convention), 1972

http://www.imo.org/en/Publications/Documents/Supplements%20and%20CDs/English/QB904E_012016.pdf

Adopted 20, October 1972, London

Date of entry into force: 15, July 1977

It defines rules aimed at preventing collision at sea, defining, among others, the duty of care and the standards for good seamanship. The definition of vessel - as every description of water craft, including non-displacement craft and seaplanes, used or capable of being used as a means of transpiration on water - may exclude from its scope of application some unmanned maritime vehicles, depending on their features. 

International Convention for the Prevention of Pollution from Ships (MARPOL Convention), 1973/78

http://www.imo.org/en/Publications/Documents/Supplements%20and%20CDs/English/QD520E_092015.pdf

Adopted 2 November 1973, London; 1978 Protocol, 1997 Protocol 

Date of entry into force: 2 October  1983

The Convention defines ships as a vessel of any type whatsoever operating in the marine environment, and includes hydrofoil boats, air-cushion vehicles, submersibles, floating crafts, and fixed or floating platforms.  Submersibles are mentioned in the Convention, which may induce one to argue that it applies to unmanned underwater vehicles, especially, if they are capable of discharging pollutants. The application of the Convention to other unmanned maritime vehicles depends on the specific features of the vehicles themselves and whether or not they fit in the technical standards provided for in the annexes.

International Convention for the Safety of Life at Sea (SOLAS Convention), 1974

http://www.imo.org/en/about/conventions/listofconventions/pages/international-convention-for-the-safety-of-life-at-sea-(solas),-1974.aspx

Adopted 21 November 1974, London

Date of entry into force: 25 May 1980

Date of entry into force in Portugal: 7 February 1984

The Convention sets for the minimum standards regarding construction equipment and operation of ships, aimed at primarily ensuring the safety of life physical integrity of those who are onboard. Accordingly, many of its dispositions are not applicable to unmanned maritime vessels and vehicles.

United Nations Convention on the Law of the Sea, 1982

http://www.un.org/depts/los/convention_agreements/texts/unclos/unclos_e.pdf

Adopted 10 December 1982, Montego Bay

Date of entry into force: 16 November 1994

Referred as the “constitution for the oceans” the United Nations Convention on the Law of the Sea aims to settle, in a spirit of mutual understanding and cooperation, all issues relating to the law of the sea and to promote the equitable and efficient utilization of the marine resources. The Convention establishes the main principles and rules regarding marine scientific research, such as the rights and duties of the States. Marine scientific research activities carried out through unmanned maritime vehicles shall then comply with the Convention, namely Part XIII. The Convention lists the powers and duties of the States over vessels flying its flag. It is argued that these powers and duties shall apply to unmanned maritime vehicles. The Convention also determines the powers of the coastal State regarding the prevention of pollution from vessels. These provisions are to be applicable, in principle, to unmanned maritime vessels. The legal regime of surveillance activities at sea is also regulated within the Convention and depends on the maritime area where the operation is carried out. The utilization of unmanned maritime vehicles in surveillance activities is subject to the rules of the Convention established for each maritime area.

Draft Convention on the Legal Status of Ocean Data Acquisition System, Aids and Devices (ODAS), of the Intergovernmental Oceanographic Commission of UNESCO, 1993

http://unesdoc.unesco.org/images/0009/000979/097992eb.pdf

Not yet in force

It has never been subject to adoption. The draft convention establishes several rules applicable to equipment used for the purpose of collecting data and information from the marine environment. It also regulates the legal regime that applies to different maritime zones.