Many legal words include silent letters. For example, what possible reason could there be for including a "c" in the word "indict" or a "b" in the word "doubt"? The inclusion of these seemingly useless letters is neither arbitrary nor capricious. These unvoiced letters are there for a reason and in some cases that reason is the Latin language.
The word "indict" is derived from the Latin words in and dictare, meaning against and declare. Thus, an indictment is a declaration against someone. In Anglo-French, the word lost the "c" and became enditer. Four or five hundred years ago, however, English scribes began to focus on the Latin origin of many English words. Thus, they included a "c" in "indict" to align the word's spelling with the original Latin word. Similarly, "doubt" is derived from the Latin word dubitare which means to waver in opinion. Orthographers likewise paid homage to the word's Latin antecedents by including a medial "b". The prefix of the Latin word, du, conveys the sense of two (duo). Hence to be in doubt is to be in two minds.
Love of Latin is not the only reason that English has so many silent letters. Some words, such as "pseudo" and "psyche" are borrowed from the Greek language which uses a different alphabet. These words are spelt in Greek as ψεύδειν (meaning to cheat) and ψύχein (meaning to blow). To transliterate these Greek words into the Latin alphabet, English writers employed a combination of "p" and "s" to stand in for the Greek letter ψ. In other cases, silent letter are diacritical, such as the silent "e" placed at the end of a word to signify a change in pronunciation - e.g., "ton" and "tone".