Conscription is enshrined in the art. 31 of the Constitution, which states: "The obligations of Mexicans are.... (II) To be present on the days and hours designated by the municipality in which they reside, to receive civic and military instruction whcih will equip them in the exercise of their rights as citizens, give them skill in the handling of arms, and acquaint them with military discipline. (III) To enlist and serve in the National Guard, according to the respective organic law, to secure and defend the independence, the territory, the honour, the rights and the interests of the homeland, as well as domestic tranquility and order." 
The legal basis of conscription is the 1942 National Military Service Act.
Mexico has one of the smallest armed forces relative to its population of any country. Since the armed forces are used exclusively for domestic functions it would be more accurate to describe them as the country's largest police force. 
All men between the ages of 18 and 40 are liable for military service. 
The length of military service is one year. 
Military service consists of military training on saturday mornings in the person's locality. Training mostly entails straightforward marching and drilling in parks or streets. Military training not necessarily dispenses with weapons or uniforms. This can vary from training centre to training centre and depends on local commanders.  
Military service exists more or less alongside the regular armed forces. 
postponement and exemption
Postponement is possible for students, those living abroad, those serving a prison-sentence in the year they turn 18, and those who have to support a family. Postponement is usually allowed for five year periods. 
Exemption is possible for medical reasons, for those living abroad and for those living more than 20 kilometers from the training centre boundaries. 
Call-up for medical examination and registration at the nearest registration centre takes place at the age of 17. Selection of conscripts is by ballot. People picking a white ball get directed to training centres and must undergo military training; people picking a black ball are not enlisted. According to the Mexican government: "Those who obtain a black ball in the draw shall fulfil their military service through availability, without having to present themselves physically for service."  
The legal minimum age for voluntary enlistment is 16. 
2 Conscientious objection
The right to conscientious objection is not legally recognized.
The Mexican government stated in 1994: "Mexican legislation does not recognize the concept of conscientious objection to military service. For those who are required to perform national military service as one of their obligations as Mexican citizens, it considers that the collective interest in defending the nation must prevail over the private interests of individuals." 
There are no known cases of conscripts stating they are conscientious objectors.
According to the Mexican government: "To date there have been no cases of consientious objection to military service, since Mexicans are conscientious about performing their military obligations as citizens and there is no legislation in this regard." 
The first generation of members of the Mennonite community arriving in Mexico were exempt from military service by a 1942 National Defence decree. It is not known whether they were exempt because of their possible refusal to perform military service. The government stated in 1990 that Mennonites born in Mexico are not exempt from military service.  
3 Draft evasion and desertion
Draft evasion and desertion are punishable under the Code of Military Justice. 
After registration for military service all young men receive the military service card (cartilla del servicio militar), an official identification document proving completion of (or exemption from) military service. For those selected to perform military service the card is only stamped after completing military service.  
Not having a valid military service card can cause difficulties in later life, for example when changing employment or address. Until the age of 40 the card is required when applying for (or renewing) a passport. The military service card must also be shown when applying for a job with the government.   
Such control of the population seems to be the government's main reason for retaining military service.  
There are not many known cases of desertion from the armed forces. It must be noted though that the military juridicial proceedings are not open to public scrutiny, as the Mexican military establishment is very secretive and interprets its rule of conduct as being outside of the public domain. 
According to one source, desertion cases are rare and, when desertion happens, the common practice is not to track down deserters. There has been some rumor of desertion cases in relation to the Chiapas uprising in 1994. 
6 Annual statistics
The armed forces are 175,000 strong, that is about 0.19 percent of the population. 
Every year about 975,000 men reach conscription age. There are 60,000 conscripts in the armed forces. 
 Brett, Derek 1994 Conscientious objection to military service. Quaker Peace and Service, Geneva.  UN Commission on Human Rights, 1994. Report of the Secretary-General prepared pursuant to Commission resolution 1993/84 (and Addendum). United Nations, Geneva.  Niessen, Robert 1994. 'Dienstplicht alleen op zaterdagochtend', in: Twintig, september 1994. VVDM, Utrecht, Netherlands.  DIRB, 1 February 1996  Amnesty International 1991. Conscientious objection to military service. AI, London.  US Immigration and Naturalization Services 1995. Mexico Profile, INS, Washington DC.  DIRB, 27 March 1990  DIRB, 20 January 1996  DIRB, 1 February 1996.  Institute for Strategic Studies 1997. Military Balance 1997/98. ISS, London.