JetBlue Airways could raise fares on some routes by up to 40% if it succeeds in buying Spirit Airlines and eliminating the low-fare carrier as a competitor on those routes, according to lawyers who are suing the airline to block the deal. The estimations were contained in court filings made earlier this week, and which JetBlue says were not properly redacted. JetBlue said Thursday that the filings are based on the opposition lawyers' interpretation of evidence, and are taking facts out of context. Consumer advocates jumped on the news, saying that the accidental disclosure supports the Justice Department's antitrust lawsuit aiming to block JetBlue's $3.8 billion purchase of Spirit, the nation's largest discount airline. Even before the government lawsuit, lawyers for about two dozen consumers sued JetBlue and Spirit last November in U.S. district court in Boston, claiming that the merger would reduce competition and lead to higher prices.