说英国没有宪法我是难以苟同的，英国没有成文宪法，却有大量宪法性质的法案及惯例，由中世纪一直存留至今。其中不得不提的是公元1215年公布的《大宪章》。《大宪章》原意是皇室与反叛地方诸侯（Baron， 男爵) 的和平条约，明文订定国会的权力和职能、地方与皇室的关系、权力与义务等等，是英国法律的重要基础。1689年《权利法案》，除了进一步加强国会权力（例如不经国会批准的税收属于违法；定期召开国会、国会内辩论内容不受检控和盘问），还在一定程度上保障国民的权利，例如未经定罪所处的刑罚属于非法等。1832年《改革法案》授予大部分男性投票权，象征民主不独由议会掌握，议会也需要由国民授权，代表他们议政；1928年《人民代表法案》，不论男女，授予全体21岁或以上国民以投票权。1911和1949年《国会法案》进一步加强由选举产生的下议院（平民）的权力，无需上议院（贵族）通过也可以通过立法草案成为正式法案。
可以见到，英国的宪制性法案是按历史的发展循序渐进发展、逐步完善的。英国《独立报》报道过，为什么英国没有成文宪法。节录如下：
The Big Question: Why doesn’t the UK have a written constitution, and
Thursday 14 February 2008
Jack Straw has used a visit to Washington to hint that Britain could finally get a written constitution spellin out citizens’ rights and codifying this country’s political system. The Justice Secretary is already working on a new Bill of Rights and Responsibilities, clearly defining people’s relationship to the state, as part of a wide-ranging package of constitutional reform. But he has, for the first time, also said the Bill could be a step towards a full written constitution to “bring us in line with the most progressive democracies around the world”.Why don’t we have a written constitution?
Essentially because the country has been too stable for too long. The governing elites of many European nations, such as France and Germany, have been forced to draw up constitutions in response to popular revolt or war.Great Britain, by contrast, remained free of the revolutionary fervour that swept much of the Continent in the 19th century. As a result, this country’s democracy has been reformed incrementally over centuries rather than in one big bang. For younger countries, including the United States and Australia, codification of their citizens’ rights and political systems was an essential step towards independence. Ironically, several based their written constitutions on Britain’s unwritten version.
该报的观点就是英国长期以来处于政治稳定的状态，大量传统、案例、习惯长久以来为全国接受和遵行。不像欧洲大陆因革命、战争产生新国家，为了尽快订立新秩序，就需要草拟成文宪法。2008年，时任英国司法大臣兼大法官的施仲宏（Jack Straw) 在美国乔治华盛顿大学演讲【1】，对英国宪制做了一个注脚：
“The constitution of the United Kingdom exists in hearts and minds and habits as much as it does in law.”
（联合王国宪法存在于人们的心思、意念和习惯里，与法律并存）
有人也许会问，以前没有，以后就不能有一部成文宪法了吗？原来英国也为此辩论了好多年，如大英图书馆在《大宪章》颁布800周年的介绍中提到：
Britain’s unwritten constitution
Should the UK have a written constitution?
The question then arises in this 800th anniversary year — should the UK now take steps to codify all its laws, rules and conventions governing the government of the country into one comprehensive document, ‘a new Magna Carta’? The case for a written UK constitution has been debated at our universities and by politicians of all parties for several decades and has been the subject of a House of Commons committee inquiry during the 2010–15 Parliament.
这事情也不是纯学术讨论，上面提到下议院一个听证会也曾经讨论过订立新宪章的问题。大英图书馆也委婉地表达为何订立一部成文宪法困难重重：
If a written constitution for the future is to be prepared, it must be one that engages and involves everyone, especially young people, and not simply legal experts and parliamentarians. Some of the mystique and charm of our ancient constitution might be lost in the process, but a written constitution could bring government and the governed closer together, above all by making the rules by which our political democracy operates more accessible and intelligible to all.
难点1：必须广泛咨询国民，尤其年轻人，不可再像以前只靠精英分子例如法律学家、国会议员来进行。潜台词就是：究竟能不能透过直接民主就新宪法内容达成共识？
难点2：恐怕在订立成文宪法的过程中挂一漏万，遗失了一些古老法案的奥妙之处。
难点1在脱欧公投上已经充分反映，搞个分手也弄得一团糟，何况订立成文宪法？所以有观点认为，既然现在没啥大事，那就按兵不动，不要搞什么成文宪法了吧。也有人认为难点2根本不合理，古老的共识、惯例压根不适合要求透明化的21世纪，例如Anthony Barnett坚定支持英国需要有成文宪法，他在《卫报》投稿【2】，说明卡梅伦推动脱欧公投的弊端及破坏性：
When David Cameron announced the referendum on 20 February, he said: “The choice goes to the heart of the kind of country we want to be … You will decide.” This compressed together all three aspects of our constitution: how power is exercised, the rights of citizens, and our aspiration as a country. When Cameron did not get the answer he wanted, Britain was turned upside down. For the Mail is right in this respect, if no other: the people have the prerogative now. Whatever the supreme court decides, “the will of the people” trumps an uncodified constitution.
基本上，英国脱欧公投就是透过2015年《欧洲联盟全民投票法案》European Union Referendum Act 2015为全民投票设立法律基础，像其他法案一样，只要国会投票通过便生效。作者认为是不是太随便了？如果有成文宪法在，便可以严密规定哪些权力通过直接民主授予、哪些由国会代表人民执行，不会由万恶的执政保守党把持民意，随意启动公投。但是，万一事情真的如此顺利，草拟好了一部成文联合王国和北爱尔兰宪法，谁来批准？英国国会下议院政治及宪制改革委员会的一份研究报告【3】指出，取得议会大多数通过之外，主流趋势是以全民投票方式，表决英国成文宪法草案：
Once a proposal for constitutional change has been devised, it requires some kind of procedure for its approval. The literature on constitution-building suggests that as well as through votes (possibly requiring super-majorities) in legislatures, there is a widespread tendency for obtaining approval (or otherwise) through referendums, though not in every case. Issues such as timing, the framing of the question and whether or not there is a super-majority requirement are likely to have a significant impact on whether or not the proposal is successfully adopted through referendum.
既有脱欧公投这样的直接民主决定国家前途的先例，表决宪法草案似乎很难回到以前的精英/代议政治由议员表决，这样又回到难点1。
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英国这老牌国家，废掉旧法比新增法律更难。
举一个简单的例子，伦敦依然有许多老旧的法律惩罚旧时认为不可接受的行为，youtube上甚至有人拍过一段短片，列举10种在伦敦的搞笑、却依然属于违法的行为。乍看起来搞笑，但也反映了要废除一条法律，在英国并不是那么容易。折中办法的就是不再执法，随它埋葬在律条里面去。
https://www.youtube.com/watch?v=rJGifTou5FE
- 行人路上携带木板，罚款500镑。法律依据：1839年《大伦敦警察法案》54章
2. 在街上唱亵渎的歌曲 。法律依据：1847年《市镇警察条文法案》第28章
3. 在冰或雪上滑行。 法律依据：1839年《大伦敦警察法案》54章
4. 在酒吧中醉酒 （哈）。法律依据：1872年《牌照法案》第12章
5. 涂物纸币。 法律依据：1928年《货币及纸币法案》第12章
6. 在公众地方放风筝。 法律依据：1839年《大伦敦警察法案》54章
7. 在离一所房子300码范围内发射大炮， 罚款200镑。1839年《大伦敦警察法案》55章
8. 敲别人家大门然后跑掉的恶作剧，罚款1000磅或监禁14天（！！！）法律依据：1847年《市镇警察条文法案》第28章
9. 早上8点后在街上拍打以清扫门口的地垫，罚款1000镑或监禁14天（！！！）。法律依据：1847年《市镇警察条文法案》第28章
10. 以惹人怀疑的手法处理三文鱼，不设上限的罚款或2年监禁。(其实原意是禁止非法捕捞）法律依据：1986年《三文鱼法案》第32章。
至于为什么困难，因为英国有超过44,000个生效法案，全靠独立机构The Law Commission（法律委员会）复核法案是否仍然适应时代，光是执行这一步已经很不容易， 然后向政府提交废除法案的建议草案，政府还需要咨询公众，避免有人因为依然按照此法案行事受到影响。如无人反对则交国会通过废除旧法案。自1965年，法律委员会已经废除了超过3,000条过时法案，单在2015年已经废除了200条。详情请看：
https://www.lawcom.gov.uk/our-work/statute-law-repeals/
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參考資料：
【1】A. (2015, December 03). Jack Straw – 2008 Speech at George Washington University. Retrieved October 15, 2018, from
Jack Straw – 2008 Speech at George Washington University
【2】 Barnett, A. (2016, November 30). Why Britain needs a written constitution.The Guardian. Retrieved October 15, 2018, from
Why Britain needs a written constitution | Anthony Barnett
【3】 Blick, A., Dr. (2011, February). Codifying – or not codifying – the UK constitution: A Literature Review. Retrieved October 14, 2018, from
https://www.parliament.uk/pagefiles/56954/CPCS%20Literature%20Review%20%284%29.pdf
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