user10105: There are many monks who are engaging in many political activities such as riots and other types of embarrassing activities in certain countries.
What are the Vinaya Rules on these? It would be great if sources are provided. 

user10100: Bikkhu can advise laymen about  politics, for the example, see "Conditions of a Nation's Welfare" in mahāparinibbānasutta. 
And saṅgha means "group of bikkhu".
Another, all virtual (sīla), keeping-sīla (ethic) and avoiding-sīla (precept), are politic because of "10 purposes of monastic legislation:for the lastingness of the true doctrine", so all advising about physical action & speech are politic, too.
However, bikkhu maybe offense vinaya, if the advising or action is wrong, conflicted with vinaya, such as ordering to kill or ordering to stole, etc.

user-1: Akila Hettiarachchi, and those with interest,
Taking side and to even maintains ones livelihood by such means is a heavy offense, when it falls under the rule given as Sanghadisesa 13, which, if a monk does not change his ways, could/should lead even to be banned from the community. (See disciplinary transactions).
If on ordering or suggesting, e.g. by means of speech, with words, signs, letter, gesture, he moves people to act on it, saying "it would be good to kill, beat, derive, ban... those/him, her...", he did beak the certain rule for each case, if it is done on that account. In the case of killing, he would have transgressed a downfall rule, Pārājika 3, or if possession if taking on his account, Pārājika 2. In this cases, he does no more count as member of the Sangha, whether he accept, confesses or not and can no more ordain in this live.

A bhikkhu who violates any of these four pārājika rules is automatically no longer a bhikkhu. There is no need for him to go through a formal ceremony of disrobing, for the act of violating the rule is an act of disrobing in and of itself. As each of the rules states, he is no longer in affiliation, which the word-analysis defines as no longer having a single transaction (i.e., he can no longer participate in any Community meetings), no longer having a single recitation (i.e., he can no longer participate in the uposatha (see BMC2, Chapter 15)), no longer having a training in common with the bhikkhus.
Even if a bhikkhu who has violated any of these rules continues to pretend to be a bhikkhu, he does not really count as one; as soon as the facts are known he must be expelled from the Saṅgha. He can never again properly ordain as a bhikkhu in this life. If he tries to ordain in a Community that does not know of his offense, his ordination is invalid, and he must be expelled as soon as the truth is found out.

A serious matter, than many activists, not only from the independent kammic effect underestimate. (Think on issues like abortion, euthanasia... as political matters for example).
If arguing for such "popular" things, to make certain groups a favor, to gain, keep, have them as possible supporter, even if a lager community does, uses such means to stay established, it's in the frame of Sanghadisesa 13, if not directly urge for actions but give signs or words of taking side. Many, so called "political correctness" packed in single or public teaching cover such. It touches also the matter of speaking for or against political parties, or single politicans, kings, groups, or what ever, might they called broadly good or bad, as a matter of favor.
To count faults of lay people, for example, is also touching another rule which forbids doing such, and if doing for a favour, to maintain one livelihood, again Sg13.
It's difficult today, where most monks are actually normal citizens (householder), are even voting on elections and hold on common rights, to find such not involved.
A Bhikkhu, taking certain side or "trades" in ways improper for a recluse, living on alms of the country, to do what ever favor to maintain his suppoter or gain estimate is called "corrupter of families".
Today many monks and even whole communities are actually living in improper relation to certain families, depending on this or that village... group of supporter. Since many live in this or that way in improper ways, doing favors for support, it's seemingly not often the case that there is less urge by fellows in this regard and so a growing serious problem. The fact that there are actually less commentaries shows that this problem has obiviously a long history and today you may often hear about certain heros or bad guys in robes, or whole communities in what ever daily media.
For lay people such things appear often pleasing and welcome and certain undertakings like "feed the hungry", "Take side for animals", "Vegerarism", till "pro abortion", social activities, charities... till very sensible political issuse are often used to catch people at large or small to have supporter.
The biggest problem with it is, that all leads astray of the Dhamma, not to speak of the holly life and destructs of course possible way for those using the good name of the tripple Gems proper.
It does good to stay in good distance if seeing that monks engage in wordily issues and politic, how ever pleasing the certain issue might appear for oneself. It's simply not their business and makes the Sangha appear as damgerous today for those, tomorrow for others.
Where ever such involvements appear, be clear that it is a "hot iron"
The link and the commentaries will give certain further ideas, understanding and references to Suttas as well. Since it is such a broad topic, it's not easy to understand, if not understanding the "economy of the Noble Ones" and the purpose of the Sangha and the holly life well, and needs a lot of explainings in such cases.
Feel how ever free to ask or raise a case, since it is good if many monks see that there are actually people who like to support and learn form a group that walk a different way then the world.
A very good explaining of how even you can addopt the ways of the Noble Ones, yet still involved and with certain duties for depending on certain communities, enjoying the benefits from it, is found in the essay "Wisdom over Justice"
In addition, well suggested by Nyom Chris, maybe one of the many Suttas which display the conduct of a Noble One and those following: AN 10.69. The whole Tipitaka speaks about people who "have gone forth, having left home and it's issues" for a higher, more worthy aim.
Rules as such had to be set out by the Buddha, because more and more "fools" joined the community and was no longer a group of ecxcusively Noble Ones. Everybody who knows todays amouts of rules in certain countries, knows that it is impossible to give for every corrupt minds idea a special rule, and if reading the rule and because it is such a big area this "corrupers of families" the Buddha left much judgement to the acting Sangha itself. (This was added because of the claim in the discussion, that the answere does not exactly match the very specific assumed question.)
Forther reading:
[Q&A] Did the Buddha teach Engaged Buddhism?
Petition from and to the international monastic and lay Sangha
Possible edited an enlaged answer, as well as place for questions and discussions on it here.
[Note: This is a gift of Dhamma and not meant for commercial purpose or other wordily gains]

10105: <p>There are many monks who are engaging in many political activities such as riots and other types of embarrassing activities in certain countries.</p>

<p>What are the Vinaya Rules on these? It would be great if sources are provided. </p>
 10100: <p>Bikkhu can advise laymen about  politics, for the example, see "<a href="http://www.accesstoinsight.org/tipitaka/dn/dn.16.1-6.vaji.html" rel="nofollow noreferrer">Conditions of a Nation's Welfare</a>" in mahāparinibbānasutta. </p>

<p>And saṅgha means "group of bikkhu".</p>

<p>Another, all virtual (sīla), keeping-sīla (ethic) and avoiding-sīla (precept), are politic because of "<a href="http://www.84000.org/tipitaka/dic/d_item.php?i=327" rel="nofollow noreferrer">10 purposes of monastic legislation:for the lastingness of the true doctrine</a>", so all advising about physical action &amp; speech are politic, too.</p>

<p><strong>However, bikkhu maybe offense vinaya, if the advising or action is wrong, conflicted with vinaya, such as ordering to kill or ordering to stole, etc.</strong></p>
 -1: <p>Akila Hettiarachchi, and those with interest,</p>

<p>Taking side and to even maintains ones livelihood by such means is a heavy offense, when it falls under the rule given as <a href="http://zugangzureinsicht.org/html/lib/authors/thanissaro/bmc1/bmc1.ch05_en.html#sg13" rel="nofollow noreferrer">Sanghadisesa 13</a>, which, if a monk does not change his ways, could/should lead even to be banned from the community. (See <a href="http://zugangzureinsicht.org/html/lib/authors/thanissaro/bmc2/bmc2.ch20_en.html" rel="nofollow noreferrer">disciplinary transactions</a>).</p>

<p>If on ordering or suggesting, e.g. by means of speech, with words, signs, letter, gesture, he moves people to act on it, saying "it would be good to kill, beat, derive, ban... those/him, her...", he did beak the certain rule for each case, if it is done on that account. In the case of killing, he would have transgressed a downfall rule, Pārājika 3, or if possession if taking on his account, Pārājika 2. In this cases, he does no more count as member of the Sangha, whether he accept, confesses or not and can no more ordain in this live.</p>

<blockquote>
  <p>A bhikkhu who violates any of these four pārājika rules is automatically no longer a bhikkhu. There is no need for him to go through a formal ceremony of disrobing, for the act of violating the rule is an act of disrobing in and of itself. As each of the rules states, he is no longer in affiliation, which the word-analysis defines as no longer having a single transaction (i.e., he can no longer participate in any Community meetings), no longer having a single recitation (i.e., he can no longer participate in the uposatha (see BMC2, Chapter 15)), no longer having a training in common with the bhikkhus.</p>
  
  <p>Even if a bhikkhu who has violated any of these rules continues to pretend to be a bhikkhu, he does not really count as one; <strong>as soon as the facts are known he must be expelled from the Saṅgha</strong>. He can never again properly ordain as a bhikkhu in this life. If he tries to ordain in a Community that does not know of his offense, his ordination is invalid, and he must be expelled as soon as the truth is found out.</p>
</blockquote>

<p>A serious matter, than many activists, not only from the independent kammic effect underestimate. (Think on issues like abortion, euthanasia... as political matters for example).</p>

<p>If arguing for such "popular" things, to make certain groups a favor, to gain, keep, have them as possible supporter, even if a lager community does, uses such means to stay established, it's in the frame of Sanghadisesa 13, if not directly urge for actions but give signs or words of taking side. Many, so called "political correctness" packed in single or public teaching cover such. It touches also the matter of speaking for or against political parties, or single politicans, kings, groups, or what ever, might they called broadly good or bad, as a matter of favor.</p>

<p>To count faults of lay people, for example, is also touching another rule which forbids doing such, and if doing for a favour, to maintain one livelihood, again Sg13.</p>

<p>It's difficult today, where most monks are actually normal citizens (householder), are even voting on elections and hold on common rights, to find such not involved.</p>

<p>A Bhikkhu, taking certain side or "trades" in ways improper for a recluse, living on alms of the country, to do what ever favor to maintain his suppoter or gain estimate is called "corrupter of families".</p>

<p>Today many monks and even whole communities are actually living in improper relation to certain families, depending on this or that village... group of supporter. Since many live in this or that way in improper ways, doing favors for support, it's seemingly not often the case that there is less urge by fellows in this regard and so a growing serious problem. The fact that there are actually less commentaries shows that this problem has obiviously a long history and today you may often hear about certain heros or bad guys in robes, or whole communities in what ever daily media.</p>

<p>For lay people such things appear often pleasing and welcome and certain undertakings like "feed the hungry", "Take side for animals", "Vegerarism", till "pro abortion", social activities, charities... till very sensible political issuse are often used to catch people at large or small to have supporter.</p>

<p>The biggest problem with it is, that all leads astray of the Dhamma, not to speak of the holly life and destructs of course possible way for those using the good name of the tripple Gems proper.</p>

<p>It does good to stay in good distance if seeing that monks engage in wordily issues and politic, how ever pleasing the certain issue might appear for oneself. It's simply not their business and makes the Sangha appear as damgerous today for those, tomorrow for others.</p>

<p>Where ever such involvements appear, be clear that it is a "hot iron"</p>

<p>The link and the commentaries will give certain further ideas, understanding and references to Suttas as well. Since it is such a broad topic, it's not easy to understand, if not understanding the "economy of the Noble Ones" and the purpose of the Sangha and the holly life well, and needs a lot of explainings in such cases.</p>

<p>Feel how ever free to ask or raise a case, since it is good if many monks see that there are actually people who like to support and learn form a group that walk a different way then the world.</p>

<p>A very good explaining of how even you can addopt the ways of the Noble Ones, yet still involved and with certain duties for depending on certain communities, enjoying the benefits from it, is found in the essay "<a href="http://zugangzureinsicht.org/html/lib/authors/thanissaro/wisdomoverjustice_en.html" rel="nofollow noreferrer">Wisdom over Justice</a>"</p>

<p>In addition, well suggested by Nyom Chris, maybe one of the many Suttas which display the conduct of a Noble One and those following: <a href="http://www.accesstoinsight.org/tipitaka/an/an10/an10.069.than.html" rel="nofollow noreferrer">AN 10.69</a>. The whole Tipitaka speaks about people who "have gone forth, having left home and it's issues" for a higher, more worthy aim.</p>

<p>Rules as such had to be set out by the Buddha, because more and more "fools" joined the community and was no longer a group of ecxcusively Noble Ones. Everybody who knows todays amouts of rules in certain countries, knows that it is impossible to give for every corrupt minds idea a special rule, and if reading the rule and because it is such a big area this "corrupers of families" the Buddha left much judgement to the acting Sangha itself. (This was added because of the claim in the discussion, that the answere does not exactly match the very specific assumed question.)</p>

<p>Forther reading:</p>

<p><a href="http://sangham.net/index.php/topic,8111.0.html" rel="nofollow noreferrer">[Q&amp;A] Did the Buddha teach Engaged Buddhism?</a></p>

<p><a href="http://sangham.net/index.php/page,Sangha-pedition.html#english" rel="nofollow noreferrer">Petition from and to the international monastic and lay Sangha</a></p>

<p>Possible edited an enlaged answer, as well as place for questions and discussions on it <a href="http://sangham.net/index.php/topic,8221.0.html" rel="nofollow noreferrer">here</a>.</p>

<p><em>[Note: This is a gift of Dhamma and not meant for commercial purpose or other wordily gains]</em></p>
