Rather than just attacking Dexter and the Karaites, I would prefer to answer some of the main contentions of the Karaites.
Let's quote from the main Karaite website shall we?
"Karaism is the original form of Judaism as prescribed by God in the Torah."
Well, that is their main contention. That we broke off from them. One would have to ignore Anan Ben David and the actual history of Karaitism to make such a statement. But let's now hear what they beleive this original form of Judaism was.
"Karaite Judaism rejects later additions to the Tanach (Jewish Bible) such as the Rabbinic Oral Law and places the ultimate responsibility of interpreting the Bible on each individual."
I'm wondering on what basis Karaites accepted additions to the Torah. Like Isaiah, Samuel, Jeremiah, Ezekiel, Kings and Chronicles. The irony is that both the Canon of the Tanakh and the Masoretic text is accepted by Karaites. Both the Canon and the Text is based solely on the word of the Sages of Israel or the Pharisees as they might like to call us.
Karaites are strange people.
They trust the Sages to tell them both what books are the Word of G-d and also what the original text of those books was but they balk when told by the Sages what the texts mean.
Imagine that.
As for the last part of the statement " the ultimate responsibility of interpreting the Bible on each individual."
Let's see what the Bible itself has to say about this.
Nehemiah Chapter 8
5 And Ezra opened the book in the sight of all the people--for he was above all the people--and when he opened it, all the people stood up.
Simple, Ezra is opening the Book of the Torah for the people and reading it. Remember that according to Karaitism, each member of that congregation was required to interpret the Law for the themselves and disregard any explanations that they disagreed with
6 And Ezra blessed the LORD, the great God. And all the people answered: 'Amen, Amen', with the lifting up of their hands; and they bowed their heads, and fell down before the LORD with their faces to the ground.
Wow, we should all read the Torah with such fervor.
7 Also Jeshua, and Bani, and Sherebiah, Jamin, Akkub, Shabbethai, Hodiah, Maaseiah, Kelita, Azariah, Jozabad, Hanan, Pelaiah, even the Levites, caused the people to understand the Law; and the people stood in their place.
Wait a second. This group of interesting people "caused the people to understand the Law."
How is that possible? Karaitism says that each Jew should rely on his own interpretation and not the interpretations of sages like "Jeshua, and Bani, and Sherebiah, Jamin, Akkub, Shabbethai, Hodiah, Maaseiah, Kelita, Azariah, Jozabad, Hanan, Pelaiah"
Now the last part of the verse "and the people stood in their place."
That is an interesting thing to say. Because according to Karaitism, the people wouldn't be standing in their place. They would be shouting. Jumping up and down and telling Ezra and his friends that their interpretations are incorrect.
But that simply proves the ridiculousness of Karaitism.
Let's read the last verse relevant to this subject.
"8 And they read in the book, in the Law of God, distinctly; and they gave the sense, and caused them to understand the reading."
Think about what this says. Ezra and these sages "gave the sense, and caused them to understand the reading."
Ezra and the sages explained the Torah to them and the people listened.
If the Bible were written by Karaites, it would say. "And the people rejected the words of Ezra and Jeshua, and Bani, and Sherebiah, Jamin, Akkub, Shabbethai, Hodiah, Maaseiah, Kelita, Azariah, Jozabad, Hanan, Pelaiah and each man (who is responsible for his own interpretation of the Torah as we all know) walked away to his own house interpretating the Torah in whatever way he wished."
I will come on and debunk more ridiculous Karaite contentions if need be but for now I will end with one last debunking.
Here's another quote from the Karaite website. "Karaism does not reject Biblical interpretation but rather holds every interpretation up to the same objective scrutiny regardless of its source."
Hmmm. Objective scrunity for ALL Biblical interpretations regardless of its source.
Sounds interesting until you keep reading their site and you find out that Karaites actually swear a daily allegiance oath to THEIR Biblical interpretations. Including their Abib interpretation which has NO TEXTUAL BASIS IN THE WRITTEN LAW WHATSOEVER.
Doesn't sound like objective scrutiny to me.