Pale colors, such as light blue or lavender or glitter pens, may not be adequately printed and will be rejected by the document holder, such as lenders and banks or county recorders. The majority of legal documents are signed in blue or black ink. This is done to make them reproducible by B&W copying machines. If you have a color copier, you should check with the particular office where you will be submitting signatures if they require colored inks for their stamps. The only time I have seen red ink used in a legal setting is when a lawyer wants to flag certain parts of a document for review by a colleague or assistant. Otherwise, documents are signed in blue or black ink.