Um, we have some legal troubles here, and I’m surprised no one to date has pointed them out. Seems we tend to forget we are a federal government. 
First off, the federal district and circuit courts would never hear Mr. Squeedunk’s case, in all likelihood. This is because Mr. Squeedunk is being charged with an offense under the laws of the Commonwealth of Kentucky (as it has delegated the authority to make such laws to the incorporated city of East Squeedunk). Thus, Mr. Squeedunk would be tried in a state court. In Kentucky, normally violation of a municipal code is heard in the District Court, but since Mr. Schmoe was silly enough to violate a capital crime, his trial would be in Circuit Court (we will ignore for the duration of commentary the fact Kentucky likely has laws which prevent East Squeedunk from making municipal code violations capital offenses, not to mention the whole Eighth Amendment issue
).
Now, if Mr. Schmoe is lucky enough to have a good attorney, he will raise the constitutional issue at the trial. Let us for the nonce assume he does so, but the trial judge rules that the statute does not violate the First Amendment (in the opinion of the judge, wearing purple is not ‘speech’, it’s just bad fashion). Following his conviction, Mr. Schmoe will appeal his conviction. Ignoring for the moment the fact he has been sentenced to death, which might force his appeal directly to Kentucky’s Supreme Court, his appeal would be to the Kentucky Court of Appeals (of which there are seven districts). Because of the seriousness of the case, he likely has an appeal by right, meaning the appellate court can’t turn down his attempt to get a ruling on the issue: they have to rule on the merits of the appeal. Assuming that they agree with the Circuit Court judge, Mr. Schmoe now is forced to file an appeal with the Supreme Court of Kentucky. Kentucky, it seems, has a case on point, since the Supreme Court of Kentucky addressed a similar case in regards to Section 1 of the Constitution of the Commonwealth of Kentucky, which guarantees to all ‘men’ “Fourth: The right of freely communicating their thoughts and opinions.” In Bfstsplk v. Commonwealth of Kentucky, the court had previously ruled that the state provision did not preclude the reactionary village of North Nimby from passing a law precluding the painting of one’s car blue. Thus, the Supreme Court of Kentucky denies Mr. Schmoe’s appeal, asserting (with some asperity) that blue is blue and it isn’t communication (apparently ignoring Mr. Schmoe’s reasoning that cars aren’t shirts, a crucial distinguishing factor in his mind). As there is no case on point from the US Supremes, the Kentucky court applies its own reasoning to the federal constitutional issue as well.
Which means, then, that the case the Supreme Court of the United States is presented with is “Joe Schmoe, Petitioner v. East Squeedunk, Respondent, Petition for Writ of Certiorari”. The Supreme Court of the US has been itching for years to address conflicting concepts about blue and clothing (and we aren’t talking Ritz here, either…). So it grants Mr. Schmoe’s petition, hears arguments, and issues the now famous decision Schmoe v. East Squeedunk, ___ U.S. ___ (2001), in which it rules 5-4 that the decision of the Supreme Court of Kentucky is incorrect as regards the federal constitution and vacates the result and remands the case to the Kentucky courts for further procedings not inconsistent with its decision. Kentucky gives up, frees Mr. Schmoe, who celebrates by sponsoring an exhibition of works by Picasso to be hung in the halls of the Supreme Court of Kentucky.
Now, this is not the only way Mr. Schmoe could have gotten in front of the US courts after his conviction for Friday Blueing. He might file a Petition for Writ of Habeas Corpus before the local federal District Court, asserting that the law in question violated the US Constitution, having failed for some reason to raise this before the state courts. This is the traditional ‘second bite of the apple’ used by those condemned to death for appealing the conviction by the state courts. There are other federal writs that can conceivably be used, but generally speaking, it isn’t a good idea to fail to raise a basic issue at trial.
What, then, does this mean for East Squeedunk? Well, they can leave the law on the books; it just can’t be applied. The courts in Kentucky will still follow the federal law most of the time.
Indeed, any attempt by East Squeedunk to apply the law to anyone else likely would result in a Petition for Writ of Mandamus filed with either the federal or state courts to order East Squeedunk to stop acting illegally.
As for Otis Kloghorn, his case will depend in large measure on what the opinions by the justices of the Supreme Court of the United States said. If five justices agreed that the First Amendment protects the wearing of colored clothing as a method of ‘expression’, West Grizzle is likely in trouble, no matter how it attempts to distinguish the case. On the other hand, if three justices thought all colored clothing was protected, but two justices thought only Mr. Schmoe’s specific case of a blue shirt was protected (and not all colored clothing), then West Grizzle may have some room to work with.
And, of course, if after 70 years of application the rule of constitutional law laid down in Schmoe v. East Squeedunk, as modified by the decision in West Grizzle v. Cloghorn, is found to have some bad results, the Supreme Court can always change the rule, as it did in such seminal cases as Brown v. Board of Education.